Page **1** of **38**

### Spaceship Discussion Thread

Posted: **January 31st, 2016, 4:22 am**

by **Sokwe**

There have been a large number of topics discussing spaceships and spaceship searches, so I am creating this topic to consolidate that discussion. Puffer discussion can also go here.

A large collection of spaceships and other moving objects can be found

here.

A table of completed spaceship searches can be found

here.

Here are some of the previous topics on spaceships:

Large constructed spaceships should probably still have their own threads.

### Re: Spaceship Search Thread

Posted: **January 31st, 2016, 4:55 am**

by **Sokwe**

Here is a new c/5 wickstretcher and wickeater (using the same wick as the previous wickstretchers):

Code: Select all

```
x = 51, y = 150, rule = B3/S23
6b2o3b2o25b2o3b2o$7bobobo27bobobo$b2obo2b2ob2o2bob2o15b2obo2b2ob2o2bob
2o$b2obobo5bobob2o15b2obobo5bobob2o$o2bo2bo5bo2bo2bo13bo2bo2bo5bo2bo2b
o$obo13bobo13bobo13bobo$2bo13bo17bo13bo$3bo11bo19bo11bo$3bo11bo19bo11b
o$b2o2bo7bo2b2o15b2o2bo7bo2b2o$b2ob2o7b2ob2o15b2ob2o7b2ob2o$b2obo9bob
2o15b2obo9bob2o3$5b4ob4o23b4ob4o$b2o6bo6b2o15b2o6bo6b2o$b2o2bobo3bobo
2b2o15b2o2bobo3bobo2b2o$b2o3bo5bo3b2o15b2o3bo5bo3b2o$2bo13bo17bo13bo$
2bo13bo17bo13bo$2bobo9bobo17bobo9bobo$4b2o7b2o21b2o7b2o$3bob2o5b2obo
19bob2o5b2obo$3b3o7b3o19b3o7b3o$2bobo9bobo17bobo9bobo$2b2o3bo3bo3b2o
17b2o3bo3bo3b2o$2b2o2b7o2b2o17b2o2b7o2b2o$3b3ob5ob3o19b3ob5ob3o$4b2o7b
2o21b2o7b2o2$8b3o29b3o$6bob3obo25bob3obo$4b2o3bo3b2o21b2o3bo3b2o$4b2o
7b2o21b2o7b2o$5bo3bo3bo23bo3bo3bo$8b3o29b3o2$2b2o3b2ob2o3b2o17b2o3b2ob
2o3b2o$b2ob2o2bobo2b2ob2o15b2ob2o2bobo2b2ob2o$b2obobobobobobob2o15b2ob
obobobobobob2o$2bo13bo17bo13bo$3bob3o3b3obo19bob3o3b3obo2$17b3o11b3o$
20b2obo3bob2o$17bo2b2ob2ob2ob2o2bo$20bo3bobo3bo$22b3ob3o$23b2ob2o$22b
3ob3o2$19b2o9b2o$19b2o9b2o$19bobob2ob2obobo$21bob2ob2obo$18b2o2bo5bo2b
2o$18b2obo7bob2o$18bobo9bobo$22bo5bo$22bo5bo2$22b2o3b2o$21bob2ob2obo$
20b2ob2ob2ob2o$20b2ob2ob2ob2o$20b2obo3bob2o$20b2obobobob2o$23bobobo$
20bobob3obobo$20bo9bo$20bo2bo3bo2bo$23bo3bo$20bob2o3b2obo$20bo9bo$22b
3ob3o$23b2ob2o2$24bobo$24bobo$22bo5bo$23b2ob2o$23b2ob2o2$23bo3bo$24bob
o$22bobobobo$23b2ob2o$23b2ob2o2$24bobo$24bobo$22bo5bo$23b2ob2o$23b2ob
2o2$23bo3bo$24bobo$22bobobobo$23b2ob2o$23b2ob2o2$24bobo$24bobo$22bo5bo
$23b2ob2o$23b2ob2o2$23bo3bo$24bobo$22bobobobo$23b2ob2o$23b2ob2o2$24bob
o$24bobo$22bo5bo$23b2ob2o$24bobo$22b2o3b2o$20bo3bobo3bo$19b2o3bobo3b2o
$19b2ob2o3b2ob2o2$21bobo3bobo$20bo3bobo3bo$24bobo$19b2o3bobo3b2o$17b2o
bobobobobobob2o$24bobo$23b2ob2o$24bobo$21b2obobob2o$21b2obobob2o$22bob
obobo$23b2ob2o$24bobo4$23b5o$23bobobo$23b2ob2o$23b2ob2o2$20b3o5b3o$22b
o5bo$19bo3bo3bo3bo$19bo4bobo4bo$19bo11bo$19b5o3b5o!
```

And a possibly new spider tagalong:

Code: Select all

```
x = 61, y = 23, rule = B3/S23
9bo7bo25bo7bo$3b2obobob2o3b2obobob2o13b2obobob2o3b2obobob2o$3obob3o9b
3obob3o7b3obob3o9b3obob3o$o3bobo5bobo5bobo3bo7bo3bobo5bobo5bobo3bo$4b
2o6bobo6b2o15b2o6bobo6b2o$b2o9bobo9b2o9b2o9bobo9b2o$b2ob2o15b2ob2o9b2o
b2o15b2ob2o$5bo15bo6bo3bo6bo15bo$28b2ob2o3$29bobo$28bo3bo$27bo2bo2bo$
29b3o$29bobo$28bo3bo$25b2o7b2o$25b2o7b2o$24b2o2b2ob2o2b2o$26b2o5b2o$
23bo2b2obobob2o2bo$24b2o2bo3bo2b2o!
```

Also, here is a c/6 tagalong for two dragons:

Code: Select all

```
x = 54, y = 36, rule = B3/S23
40b3o4b3o$40b3o4b3o4$39b5o2b5o$43bo2bo$5bo6bo28bo2b2o2bo$4bobo4bobo26b
2o6b2o$4bobo4bobo25bo10bo$5bo6bo25bo12bo2$4b3o4b3o22b3o12b3o$4b4o2b4o
11b6o6b3o10b3o$7bo2bo13bo6bo7bo10bo$4b3ob2ob3o9bo8bo6b3o6b3o$4b2o6b2o
10bo2b2o2bo10bo4bo$3b2o8b2o25bo8bo$20b3o10b3o3bo2bo4bo2bo$2bo12bo3bo3b
o8bo3bobo2bo6bo2bo$o2bo10bo2bo2bo14bo8b2o$o2bo10bo2bo4b2o8b2o4bo2bobo
2bobo2bo$44b2o$3b3o6b3o24b3o6b3o$3bo10bo25bo8bo$5bo6bo27bo8bo$3b3o6b3o
23bo3bo4bo3bo$38bo3bo4bo3bo$6bob2obo25bo2bo2bo2bo2bo2bo$7bo2bo$3bob2ob
2ob2obo$3b3o6b3o2$3bobo6bobo$3bobo6bobo$b3ob3o2b3ob3o!
```

### Re: Spaceship Search Thread

Posted: **January 31st, 2016, 5:23 am**

by **Sphenocorona**

Sokwe wrote:Also, here is a c/6 tagalong for two dragons:

Very nice, it's 114P6H1V0's front end! This allows for arbitrary extension in both dimensions:

Code: Select all

```
x = 128, y = 91, rule = B3/S23
25b6o28b6o32b6o$24bo6bo26bo6bo30bo6bo$23bo8bo24bo8bo28bo8bo$23bo8bo24b
o8bo28bo8bo$26bo2bo30bo2bo34bo2bo$25bo4bo28bo4bo32bo4bo$25b2o2b2o28b2o
2b2o32b2o2b2o4$25b6o28b6o32b6o$27b2o32b2o36b2o$25bo4bo28bo4bo32bo4bo$
26bo2bo30bo2bo34bo2bo$26b4o30b4o34b4o3$25b6o28b6o32b6o$24bo6bo26bo6bo
30bo6bo$23bo8bo24bo8bo28bo8bo$23bo8bo24bo8bo28bo8bo$26bo2bo30bo2bo34bo
2bo$25bo4bo28bo4bo32bo4bo$25b2o2b2o28b2o2b2o32b2o2b2o4$25b6o28b6o32b6o
$27b2o32b2o36b2o$25bo4bo28bo4bo32bo4bo$26bo2bo30bo2bo34bo2bo$26b4o30b
4o34b4o3$25b6o28b6o32b6o$24bo6bo26bo6bo30bo6bo$23bo8bo24bo8bo28bo8bo$
23bo8bo24bo8bo28bo8bo$26bo2bo30bo2bo34bo2bo$25bo4bo28bo4bo32bo4bo$25b
2o2b2o28b2o2b2o32b2o2b2o4$25b6o28b6o32b6o$27b2o32b2o36b2o$25bo4bo28bo
4bo32bo4bo$26bo2bo30bo2bo34bo2bo$26b4o30b4o34b4o3$25b6o28b6o32b6o$24bo
6bo26bo6bo30bo6bo$23bo8bo24bo8bo28bo8bo$23bo8bo24bo8bo28bo8bo$26bo2bo
10b3o4b3o10bo2bo34bo2bo$25bo4bo9b3o4b3o9bo4bo32bo4bo$25b2o2b2o28b2o2b
2o32b2o2b2o3$39b5o2b5o$25b6o12bo2bo12b6o32b6o$5bo6bo14b2o12bo2b2o2bo
12b2o14bo6bo14b2o14bo6bo$4bobo4bobo11bo4bo9b2o6b2o9bo4bo11bobo4bobo11b
o4bo11bobo4bobo$4bobo4bobo12bo2bo9bo10bo9bo2bo12bobo4bobo12bo2bo12bobo
4bobo$5bo6bo13b4o8bo12bo8b4o13bo6bo13b4o13bo6bo2$4b3o4b3o22b3o12b3o22b
3o4b3o28b3o4b3o$4b4o2b4o11b6o6b3o10b3o6b6o11b4o2b4o11b6o11b4o2b4o$7bo
2bo13bo6bo7bo10bo7bo6bo13bo2bo13bo6bo13bo2bo$4b3ob2ob3o9bo8bo6b3o6b3o
6bo8bo9b3ob2ob3o9bo8bo9b3ob2ob3o$4b2o6b2o10bo2b2o2bo10bo4bo10bo2b2o2bo
10b2o6b2o10bo2b2o2bo10b2o6b2o$3b2o8b2o25bo8bo25b2o8b2o26b2o8b2o$20b3o
10b3o3bo2bo4bo2bo3b3o10b3o22b3o10b3o$2bo12bo3bo3bo8bo3bobo2bo6bo2bobo
3bo8bo3bo3bo12bo3bo3bo8bo3bo3bo12bo$o2bo10bo2bo2bo14bo8b2o8bo14bo2bo2b
o10bo2bo2bo14bo2bo2bo10bo2bo$o2bo10bo2bo4b2o8b2o4bo2bobo2bobo2bo4b2o8b
2o4bo2bo10bo2bo4b2o8b2o4bo2bo10bo2bo$44b2o$3b3o6b3o24b3o6b3o24b3o6b3o
26b3o6b3o$3bo10bo25bo8bo25bo10bo26bo10bo$5bo6bo27bo8bo27bo6bo30bo6bo$
3b3o6b3o23bo3bo4bo3bo23b3o6b3o26b3o6b3o$38bo3bo4bo3bo$6bob2obo25bo2bo
2bo2bo2bo2bo25bob2obo32bob2obo$7bo2bo68bo2bo34bo2bo$3bob2ob2ob2obo60bo
b2ob2ob2obo26bob2ob2ob2obo$3b3o6b3o60b3o6b3o26b3o6b3o2$3bobo6bobo60bob
o6bobo26bobo6bobo$3bobo6bobo60bobo6bobo26bobo6bobo$b3ob3o2b3ob3o56b3ob
3o2b3ob3o22b3ob3o2b3ob3o!
```

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 4:32 pm**

by **HartmutHolzwart**

Congratulations! This is really progress! How did you search for this? Can we expect more?

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 5:15 pm**

by **Sokwe**

HartmutHolzwart wrote:Congratulations! This is really progress! How did you search for this? Can we expect more?

The new c/5 orthogonal wickstretcher was found by doing a width-17 reverse gfind-pt search starting from the known wick (following

these instructions). obviously no width-17 symmetric stretcher exists, but I checked the partial results every once in a while, and I eventually found one that could be supported by two domino sparks.

The c/6 orthogonal tagalong was found with with WLS after noticing the following reaction in a modified gfind search:

Code: Select all

```
x = 14, y = 8, rule = B3/S23
6b2o$4bo4bo$3bo6bo$2bo8bo$2b2ob4ob2o2$2o10b2o$2o10b2o!
```

I tried a short, wide search and quickly found the domino spark support.

I haven't worked with either of these searches since I posted these results.

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 5:21 pm**

by **muzik**

I'm all for new spaceship velocities.

Here's a question: is it possible for a ship to exceed c/2? Yes, I know that the speed of light cannot be attained (a vertical line does, but is not a spaceship), but could a ship with a velocity of just sliiiightly over c/2 exist? Something really barely faster like 9c/16 or 1337c/2673?

And what would the slowest possible spaceship? This c/5648 thing exists, but only within a different rule:

Code: Select all

```
x = 12, y = 14, rule = B3457/S4568
4bo2bo$4b4o$2b8o$2b2ob2ob2o$obobo2bobobo$2ob6ob2o$ob3o2b3obo$3ob4ob3o$
2ob6ob2o$b3o4b3o$b3o4b3o$3b2o2b2o$3bo4bo$5b2o!
```

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 5:33 pm**

by **Sokwe**

muzik wrote:Here's a question: is it possible for a ship to exceed c/2?

No. In fact, if a spaceship with velocity (m,n)c/p exists in Conway's Game of Life (where m and n are the vertical and horizontal displacements and p is the period), then we must have m + n <= p/2.

muzik wrote:And what would the slowest possible spaceship?

We can build spaceships as slow as we want using construction techniques. For example, the original

Gemini could be slowed down by pulling the two constructors farther apart.

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 5:36 pm**

by **gmc_nxtman**

muzik wrote:Here's a question: is it possible for a ship to exceed c/2?...

It has been proven impossible for anything inside the game of life to exceed c/2 in speed, but in B2 rules it's theoretically possible.

muzik wrote:And what would [be] the slowest possible spaceship?...

There is no slowest possible spaceship, spaceships can be infinitely slow in the game of life. One can trivially modify the Gemini spaceship so as to make its construction process slightly slower. However, we have yet to find a spaceship that can be adjusted in this manner in another rule.

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 5:41 pm**

by **muzik**

Sokwe wrote:muzik wrote:Here's a question: is it possible for a ship to exceed c/2?

In fact, if a spaceship with velocity (m,n)c/p exists in Conway's Game of Life (where m and n are the vertical and horizontal displacements and p is the period), then we must have m + n <= p/2.

Wait, what?

Explain please?

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 5:42 pm**

by **muzik**

gmc_nxtman wrote:
muzik wrote:And what would the slowest possible spaceship [be]?...

There is no slowest possible spaceship, spaceships can be infinitely slow in the game of life. One can trivially modify the Gemini spaceship so as to make its construction process slightly slower. However, we have yet to find a spaceship that can be adjusted in this manner in another rule.

well, to rephrase that: What would the slowest orthogonal spaceship be?

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 6:09 pm**

by **Sokwe**

muzik wrote:Sokwe wrote:If a spaceship with velocity (m,n)c/p exists in Conway's Game of Life (where m and n are the vertical and horizontal displacements and p is the period), then we must have m + n <= p/2.

Wait, what?

Explain please?

Nathaniel wrote a nice article about this

here. It only shows the c/4 diagonal and c/2 orthogonal speed limits, but this method can be extended to show the claim I made above. I encourage you to think about why this is.

muzik wrote:well, to rephrase that: What would the slowest orthogonal spaceship be?

There is no "slowest orthogonal spaceship". For any speed in any direction, we can always build a spaceship that is slower than that speed. All we need to do is make a constructor based spaceship that displaces itself by a fixed amount and then performs some time-wasting activity to increase the period as much as we want. As I recall, ge

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 6:14 pm**

by **muzik**

Sokwe wrote: As I recall, ge

Well then.

Also, wouldn't it technically be possible to build a spaceship that consists of multiple other spaceships slowing each other down via some strange reaction?

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 6:16 pm**

by **biggiemac**

Regarding the upper speed limit:

c/2 is the orthogonal speed limit, at least for a spaceship propagating in empty space. There are ways to make faster propagation within a fixed background, see for example the discussions of

signals or Gabriel Nivasch's discussion of lightspeed signals

here. But to be called a spaceship it needs to have emptiness in front of and behind it.

Regarding the lower: isn't the Waterbear exactly what you said: "a spaceship that consists of multiple other spaceships slowing each other down via some strange reaction"?

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 6:21 pm**

by **muzik**

biggiemac wrote:Regarding the upper speed limit:

c/2 is the orthogonal speed limit, at least for a spaceship propagating in empty space. There are ways to make faster propagation within a fixed background, see for example the discussions of

signals or Gabriel Nivasch's discussion of lightspeed signals

here. But to be called a spaceship it needs to have emptiness in front of and behind it.

Regarding the lower: isn't the Waterbear exactly what you said: "a spaceship that consists of multiple other spaceships slowing each other down via some strange reaction"?

Indeed, but it's not an orthogonal spaceship. Those are my main interests.

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 6:24 pm**

by **biggiemac**

muzik wrote:Indeed, but it's not an orthogonal spaceship. Those are my main interests.

Well then you should look at the

Engineless Caterpillar thread, which was an attempt to make a recipe for any sufficiently slow orthogonal spaceship using that sort of process. I don't know why it has been inactive lately..

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 6:30 pm**

by **Sokwe**

muzik wrote:Sokwe wrote: As I recall, ge

Well then.

Sorry, I started writing a sentence, but I decided against it. Unfortunately, I forgot to delete what I had written. What I was going to say was that, from what I recall, the original Gemini design allowed for the construction of arbitrarily slow orthogonal spaceships.

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 6:33 pm**

by **muzik**

Sokwe wrote:muzik wrote:Sokwe wrote: As I recall, ge

Well then.

Sorry, I started writing a sentence, but I decided against it. Unfortunately, I forgot to delete what I had written. What I was going to say was that, from what I recall, the original Gemini design allowed for the construction of arbitrarily slow orthogonal spaceships.

That makes sense. What's the fastest speed you can make one of those construct at?

Also, isn't

blinker technically the slowest spaceship? It moves at 0c/1

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 7:56 pm**

by **Sokwe**

muzik wrote:Also, isn't

blinker technically the slowest spaceship? It moves at 0c/1

It depends on how you define "spaceship". Typically, spaceships are defined to have some non-zero displacement.

muzik wrote:What's the fastest speed you can make one of those [Gemini] construct at?

For the original design, I

*think* the speed of a ship with a velocity (m,n)c/p is limited by 4*m+576*(m+n)/2 < p and m > n > 0.

Disclaimer: the following analysis is not guaranteed to be correct.

Consider the original Gemini design travelling up and left (the same orientation that the original Gemini was posted in). Let m be the vertical (upward) displacement and let n be the horizontal (leftward) displacement. In the original Gemini there are two independent construction arms. The circuitry for each construction arm has a repeat time of 576 generations. That is, one "cycle" of the circuitry takes 576 generations. During each cycle, the ends of each construction arm can be pushed diagonally by one cell. After a push of either of these construction arms, it takes an extra 4 generations for the next set of gliders to reach the end of the construction arm.

Let A be the number of pushes in the up-left direction, and let B be the number of pushes in the up-right direction. Notice that m=A+B and n=A-B. Notice also that A >= B since we assumed the ship was traveling left. Then the total period of the Geminoid is

Code: Select all

```
p = 4*(A+B) + 576*max{A,B} + C
= 4*(A+B) + 576*A + C
= 4*m + 576*(m+n)/2 + C
< 4*m + 576*(m+n)/2
```

where C is the constant time it takes to build the new construction arms and destroy the old ones.

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 8:35 pm**

by **Sphenocorona**

On a similar note, it is theoretically possible to produce any rational spaceship velocity with 'absolute speed' (ie. the speed compared to the fastest possible information transfer with the same slope) less than or equal to c/2, if it is possible to slow-salvo construct a c/2 puffer for the 2c/3 blinker fuse. c/2 orthogonal and c/4 diagonal have explicit examples, and any slower speed could be constructed by sending out such a puffer above, ignite it, and shoot *WSS salvos at it. This also assumes that slow *WSS salvos are capable of universal construction though, which is likely.

### Re: Spaceship Discussion Thread

Posted: **February 18th, 2016, 10:21 pm**

by **FractalFusion**

Sokwe wrote:muzik wrote:Sokwe wrote:If a spaceship with velocity (m,n)c/p exists in Conway's Game of Life (where m and n are the vertical and horizontal displacements and p is the period), then we must have m + n <= p/2.

Wait, what?

Explain please?

Nathaniel wrote a nice article about this

here. It only shows the c/4 diagonal and c/2 orthogonal speed limits, but this method can be extended to show the claim I made above. I encourage you to think about why this is.

To add to that, in Life, no pattern can ever "grow out" to the next half-diagonal in two consecutive generations (for details, see Nathaniel's article). It helps to think of a diagonal line of slope -1 that lies above a pattern and moves upward one cell every two generations, and the pattern can never cross this line. The c/4 diagonal, c/2 orthogonal, and m + n <= p/2 speed limits immediately follow from this.

Other cellular automata may have different speed limits. A B3 rule with S4 or S5 may have diagonal speed up to c/3, and orthogonal speed is still limited to c/2 (in this case, the bounding line has slope -1/2 and moves upward one cell every two generations, or alternatively moves rightward one cell every generation). B2 rules have max c/2 diagonal and c orthogonal, and B1 rules have growth of c in every direction (of course, no spaceships).

There was also a

previous topic on this site about spaceship speed limits.

### Re: Spaceship Discussion Thread

Posted: **February 19th, 2016, 7:13 am**

by **calcyman**

Sphenocorona wrote:... less than or equal to c/2 ...

Wait -- I can see how to get any speed strictly less than c/2 (by l_1 metric), but how do you handle the equality case? In particular, I don't think you've proved that there exists a (2, 1)c/6 spaceship.

### Re: Spaceship Discussion Thread

Posted: **February 20th, 2016, 2:08 pm**

by **moebius**

I like the new thread. It is more convenient, as I have a variety of stuff.

I did some more 4c/10 glide symmetric searches. At width 17 there are no period 10 ships with a period 10 front row. There are many period 5 tags to sift through in hopes of finding period 10 extensions. I checked a lot of the period 5 tags, though certainly not all of them. I was hoping to find a large period 10 section, but none were to be had. I did find the following period 10 glide symmetric ship. It actually has a width 19 spark, as knight3 only restricts the width on 2 of the 5 phases for this search.

Code: Select all

```
x = 17, y = 57, rule = B3/S23
5bo5bo$4bobo3bobo$3b2ob2ob2ob2o$3bo2bo3bo2bo$b2ob2o5b2ob2o$2b2o9b2o$3b
2o7b2o$4bo7bo$b2o11b2o$2b3o7b3o$5bobobobo2$8bo$7bobo$7bobo$6bo3bo$6b5o
$5bo5bo$4b3o3b3o$5bo2bo2bo2$5bo5bo$3b3o5b3o2$4bo7bo2$4bobo3bobo$4b3o3b
3o$3b2o2bobo2b2o$4bob2ob2obo$2b2o3bobo3b2o$2bob2obobob2obo$3b2o7b2o$4b
o7bo$b2obo2bobo2bob2o$b2obobo3bobob2o$4b2o5b2o$3bo9bo$2b2o9b2o$5b2o3b
2o$4b3o3b3o$3bobo5bobo$3b2o7b2o$2b2o9b2o$bo13bo$o2b3o5b3o2bo$bo3bo5bo
3bo$3b2o7b2o$bobo3b3o3bobo$2o5b3o5b2o$2o5bobo$o$bo4bo3bo$6b5o2$5bobobo
bo$6bo3bo!
```

Using knight2 I did a variety of 2c/8 glide symmetric searches. Again, I was hoping to find a pure period 8 ship but none have shown up. My width 18 search for ships with a period 8 front row is nearing completion and it appears that it will end with no ships found. I did notice a partial that had an even symmetric period 4 end. It took me an hour to set up and ten minutes to run to find a width 24 completion.

Code: Select all

```
x = 24, y = 47, rule = B3/S23
10bo$9b2o3bo$8b2ob3obo$10bo2b3o$10bob3o$13b2o$12b2o$12bo$10bo$10bo3bo$
8b4o3bo$7bo4b2o2bo$7b2obo5bo$10b2o2b3o$10b2o$7b2o2b5o$5b2ob4o3bob2o$6b
4obo3b4o$10b2o5b3o$10bo4bo$10bo$10b2obobo$10b2o$10b2o3bo$11bo$4bo14bo$
3b2ob2o8b2ob2o$4bo3bo6bo3bo$3bo2bob8obo2bo$3bob2o3bo2bo3b2obo$6bobo6bo
bo$3bo3b2o6b2o3bo$2bo18bo$b3o5bo4bo5b3o$bobobo3bo4bo3bobobo$b2o5bo6bo
5b2o$obo18bobo$3bo16bo$3bo16bo$3bo16bo$bo2bo14bo2bo$2b3o14b3o$4bo14bo
2$4b2o12b2o2$4b3o10b3o!
```

When trying to look for period 8 tags of period 4 ships at width 15 the following ships showed up that I have not seen before.

Code: Select all

```
x = 57, y = 32, rule = B3/S23
5bo3bo37bo3bo$3b9o33b9o2$6b3o39b3o$5b5o37b5o$2b2o7b2o31b2o7b2o$b3o7b3o
29b3o7b3o$o13bo27bo13bo2$3b3o3b3o33b3o3b3o$2o11b2o27b2o11b2o$2o4bobo4b
2o27b2o4bobo4b2o$3bobo3bobo33bobo3bobo$2b2o7b2o31b2o7b2o$3bobo3bobo33b
obo3bobo$2bo2bo3bo2bo31bo2bo3bo2bo$2bobobobobobo31bobobobobobo$b3o7b3o
29b3o7b3o$b3o7b3o29b3o7b3o$2b2o7b2o30b3o7b3o$2b2o7b2o31b2o7b2o$4b3ob3o
33b2o7b2o$46b3ob3o2$5b2ob2o$5b2ob2o37b2ob2o$6bobo38b2ob2o$6b2o40bobo$
7b2o39b2o$5bo2bo40b2o$6b2o39bo2bo$48b2o!
```

I also did a 2c/6 width 21 glide symmetric search with an asymmetric period 6 front row first phase. I know that Josh Ball did a similar search and I have included his results in the following collection. Josh's ships are the fourth and fifth on the first row. All 2c/6 width 21 glide symmetric ships have either Josh's front end or my front end. The third ship on the first row I found previously and finished it off at period 3. The second ship on the first row is probably the minimum length for this type of ship. It is length 51. I will know for sure in the next few days, as the last remaining alternatives are currently at length 46. The width 21 search tree gets very wide at that length with variations on ships in the second row. At about length 28 Josh's front end necks down to ~width 13. I did a width 15 exploratory extension starting at row 28 and the results of that search are on the second row. Ships 1 2 4 5 6 7 on the second row all have backends that have been previously posted and are in jslife. I haven't seen the other backends.

Code: Select all

```
x = 261, y = 269, rule = B3/S23
6bo3bo25bo3bo25bo3bo24bo29bo29bo$5bobobobob3o19bobobobob3o19bobobobob
3o18bobo7b3o17bobo7b3o17bobo7b3o$4bo2bo4b2o2bo17bo2bo4b2o2bo17bo2bo4b
2o2bo20bo2b2obo2bo20bo2b2obo2bo20bo2b2obo2bo$5bo4b2o2b3o18bo4b2o2b3o
18bo4b2o2b3o15bo2bobobobobobobo14bo2bobobobobobobo14bo2bobobobobobobo$
7b2o6b2o20b2o6b2o20b2o6b2o14bo2bo2bobo3bobob2o12bo2bo2bobo3bobob2o12bo
2bo2bobo3bobob2o$6bobo5b2o20bobo5b2o20bobo5b2o16bo2bobobobobo2b3o13bo
2bobobobobo2b3o13bo2bobobobobo2b3o$5bo4bo2bo2bo18bo4bo2bo2bo18bo4bo2bo
2bo15bo4b3o3b2o17bo4b3o3b2o17bo4b3o3b2o$6b2ob2o5bo19b2ob2o5bo19b2ob2o
5bo16bo3bobo3bo19bo3bobo3bo19bo3bobo3bo$4b2ob2obobobo19b2ob2obobobo19b
2ob2obobobo19b3o3b2o3bo18b3o3b2o3bo18b3o3b2o3bo$3bo2b3o3b2o2b2o15bo2b
3o3b2o2b2o15bo2b3o3b2o2b2o17b3o3bo23b3o3bo23b3o3bo$2b2o7b2o4b3o12b2o7b
2o4b3o12b2o7b2o4b3o13b2o11b2o15b2o11b2o15b2o11b2o$2bob3o7bobob2o12bob
3o7bobob2o12bob3o7bobob2o12b2o6bob4o2bo13b2o6bob4o2bo13b2o6bob4o2bo$3b
2o4bo3b2o18b2o4bo3b2o18b2o4bo3b2o17bobo3bobo4bo16bobo3bobo4bo16bobo3bo
bo4bo$4b4o5bo20b4o5bo20b4o5bo17bobobobobob3o3bo2bo10bobobobobob3o3bo2b
o10bobobobobob3o3bo2bo$5bob2obob2ob2o18bob2obob2ob2o18bob2obob2ob2o14b
3ob3obobob5ob2o10b3ob3obobob5ob2o10b3ob3obobob5ob2o$6bob5o2b3o18bob5o
2b3o18bob5o2b3o12bo3b2o3bo3bo3b2o11bo3b2o3bo3bo3b2o11bo3b2o3bo3bo3b2o$
3b2obobo5bo18b2obobo5bo18b2obobo5bo23b2ob4o23b2ob4o23b2ob4o$3b2obobo4b
2ob2o15b2obobo4b2ob2o15b2obobo4b2ob2o13b2o5b4o3b2o14b2o5b4o3b2o14b2o5b
4o3b2o$2bob6o3bo2bo2bo12bob6o3bo2bo2bo12bob6o3bo2bo2bo21bo4bobo22bo4bo
bo22bo4bobo$2bob3o12bo12bob3o12bo12bob3o12bo12b2o28b2o28b2o$3b4o26b4o
9bo16b4o9bo16bo12bobo14bo12bobo14bo12bobo$7bo3bo3b2obo17bo3bo25bo3bo
20bo3bo9b3o13bo3bo9b3o13bo3bo9b3o$3bo4bo3bo5bo15b3o3b2o3b4o15b3o3b2o3b
4o11bo5bo11b2o10bo5bo11b2o10bo5bo11b2o$13b2o2bo17b2o2bobo3bo19b2o2bobo
3bo14bo5bo6bob2o2b2o9bo5bo6bob2o2b2o9bo5bo6bob2o2b2o$3b2o3bo7bobo16bo
2b2obo23bo2b2obo20bo2b2o6bobo3b2o11bo2b2o6bobo3b2o11bo2b2o6bobo3b2o$2b
2o12bob2o17bob2ob4o21bob2ob4o18b2o4bob4o18b2o4bob4o18b2o4bob4o$2b2o30b
5obo2b3o18b5obo2b3o23bobob2obo22bobob2obo22bobob2obo$2bo32bo2b2obob2o
2bo17bo2b2obob2o2bo20b2o5bo22b2o5bo22b2o5bo$2bo15b2o18bo3bob3o21bo3bob
3o21bob4o24bob4o24bob4o$b3o15bo17bo5b2o22bo5b2o22b3o27b3o27b3o$o3b2o9b
3o19bo3bo2bo22bo5b2o23bobo27bobo26b2obo$2b2o2b2o6b2o3bo16bo4b2o26bo3b
2o23bob2o26bob2o26bo2b2o$2o2bob2o4bo3b4o14b2ob2obobo2b2o19b2ob2ob2o2bo
18b2obobob4o19b2obobob4o24bobo$3b2o7bobobo2bo15bo2bobo5b2o14b2o4bobo4b
3o17bo2bobobob2o19bo2bobobob2o20b2o2bo3bo$3bobob2o2bo2bobo2bo13bo4bobo
2bob2o15b2ob2obo2bo3bobo16bo2b2obobo3bo17bo2b2obobo3bo19b2ob6o$8b2o8bo
19bobo4b3o20bo26bo3b2o3bo20bo3b2o3bo19b2o2bobo4bo$5b3ob2o5b2o14b2o2b3o
b2obo4bo15bo3b4ob2o24b2o3b2o23b2o3b2o18b2ob3o4bo$4bob2o2bobobobo16bo5b
2o3b2o3b2o14bo2bob3ob3o18bo2bobo3b2o19bo2bobo3b2o22b2o3b2o$5bo7b2obo
13b2o3bo4b6o20bo3bo4b2o19b2o28b2o29bo5bo$4b2o4b2o18b2ob3o5b3o2bob3o15b
2o7b2o25bo29bo24bo3bo$9b2o3bobo14bo3bo8b2o20bo5bobob2o21b2o28b2o26bo2b
o3bo$8b2obo2b2o16bo10bo2bo18bobo6b4o20bo2bo26bo2bo24b4o4bo$5b3o6b3o18b
obo5bo20b3o2b2o6bo20b2o2bo25b2o2bo23bob2o3bo$5bo10bo19b3o6bo17bo6b3obo
b2o25bo29bo20b2o3bo3b3o$4bo11b2o18bob4o2bo16b2ob2ob2o3bo27bobo27bobo
21b2o2b3o2bo2bo$2b2ob2o9b2o23bo20bo8b2o4bo25bo29bo19bo4b3o2bob2o$2b2o
10bo4bo15b2o2b5o2bo17b2o2b2o3b2obobo17b2obobobo22b2obobobo19bo2bo2bo3b
2o$2bo2bo9b2o3bo11b3o5bo3b4o17b2o2bo5b2o16b2ob2o3bobo2b2o15b2ob2o3bobo
2b2o19b2o5bo$2b4o10bo15b2ob2o3b2o2b2obo28b2o15b2o3b4o5bo15b2o3b4o5bo
15bo3bo5b2o$2b2o2bo8bo47b2ob2o4b2o19bo8b4o2bo14bo8b4o2bo12b2o4b2o5bo3b
2o$2b3o2bo5bobo4bo18b2o23bo3bo3b2o20bo3bo9bo15bo3bo9bo12bo15b2obo$7b3o
3b2o2bobo47bobo2bo22bo2bobo2bobo2bo16bo2bobo2bobo2bo12bo3bo11bo2bo$7b
2obobo3b3o48bo4bo21bo4bo5bobo16bo4bo5bobo15b2o14bo$6bobob2obobo49bo4bo
2bob2o18bo3b5o21bo3b5o20b2o10bo$6b3obobo50b2o3bobo4b3o18bo3bo25bo3bo
22bo11b2o$5bo4bo2bobo46b2o8bo2b2o19bo2bo26bo2bo24b2o$7b2ob2obo2bo46bo
6bobo23b2o7b2o19b2o7b2o$4bo2b3obo2b2o47bo3b2o3b2obo19bob2o3b3o20bob2o
3b3o$3bob2o4bo4b2o45b3obobobobobobo23b3o27b3o$2b2o9b4obo44bobo3bobobob
o23b2ob2o25b2ob2o$4b3o11b2o42b2obo3bo2bo2bob2o20b2obo26b2obo$4o2bobo3b
5obo42bo3bo2b2o2bo24bo2b2o25bo2b2o$2b3o2bobo3bo47bo3b2ob2ob2o6bo15bo5b
o3bo19bo5bo3bo$15b2o46bo7b2o5b2o14b2o4bo3bobo17b2o4bo3bobo$2bo3b2ob2o
3b2o46bo2bo3bob2o20bo5bo3b2ob2o16bo4bo3b2ob2o$2b2o3bobobo4b4o45bo5bo3b
o16bob2o7b2o20b3o5b2o2bo$3bobo8bobob2o44bo9b3o18b2o6b6o16bob2o4bo3bo$
4bo10b2ob2o46bob2obo2bo2bo13bob3o3bo3bo5bo12b2obob2o4b2o2bo$3b3o11b2o
44b2o5b6o14bo7bob4o2b3o13b2o3bo2b4ob4o$2b3obo7bo3bo44bobo11b2o12bobob
2o2bo2bobo22bo2bo6b3o$b2o3bo6bobo3bo43bob3o7b3o17bo3b2obobob2o15b2o6b
2o2bo2b2o$o6bo5bobo2bo55b4o16b2obo2b3o3bo16b3o8b2ob2o$bo6bo4bo5bo48b2o
4b3o16bobobo2bo3bo30bob2o$8b2o3b2o54b2obobo21bo3b4obobo27bobo$8b2o3b2o
55bob2o17b3o2b4o5b4o26bobo$8bo4bo54b2o4bo16bo9b4o4bo12b5o3bo4bob2o$6b
3o2b3o53b5o18b3ob4ob2o3bob3o16b2o3b2ob4o$8bo4bo54bo5bo15bob2o2bobob2ob
o2bo2b2o11b2o4bo2b2ob2o$6bo4bo62bo16bobo5bo2bo2bo21b3o4b2o$7bo4bo56bo
3bo21bo3b2obo23bo5b2o$62b3o4b2obo4b2o18bo2bob2o22b2o$62bobo5bobo2b2o2b
o16b3obo3bo20b2ob2ob2o$62bo8b2o2b2o18bo3b6o20bo2b2o2b4o$63b3o3b3o25b2o
2bo2bo18bobo6bo3b3o$63b4o6bobo3bo14bo2bo3bob2o16b2o4bo5b3o3bo$63bo3bob
o9bo14b4o4b2obo15bo14b2obo$64b2o5bobo2b3o17b3o5b2obo12b2o16bo$68bo3bo
2bo18bo2b3o6b2o12b2ob2o12bo$62bo3bo8bo2bo15bo6b2obobo14bobo6bo6b3o$62b
2o2b2o6b2o19bo2bo2b2o2b2o15bo6b3o4bob2o$62b3o7bo3bo20b2o3bo2b2o15bo5bo
3bo6b2o$63b2o4b4o2bo2bo16bo5bo2b2o15bo7b3o$68bo3bo2bo22b2o3bo17bo6b5o
6b2o$64bo4bobo3bobo20b2ob2o19b2o4bo3bo4bobo$65bo10b2o21bo2bo17bob2ob2o
2bobo2b2o$63b3o11b2o21bo20bo3bo2b2ob2o2bo$62b3obo6b2o26b2o20bob2o2bobo
3bob2o$64b4o5b2o22b3o2b2o18b3o3bo3bob2obo$65b2o2bo2bo22b2ob2obob2o16b
2o3b4o5b2o$67bob2obo21bobo2b5o2bo14b2o7b3o$67b3obo2bo19bobo6bo2b2o14b
2o3b4o2bo3b2o$66bo4bo3bo18bobobob3obob2o22bo2b2o2b3o$67b2o5bo27bo19b3o
3b2o3b2o$68bo4b2o22bo2b2o3bo17b3ob2obo6bo$67bobo3bo23b2o5b2o24bo3bo$
67bobo55bo3b2ob3o2bo$69bobo24bo6bo21b3o2bob2o2bo$69bo2bo22b3o4b3o26b2o
b2o$68bo3bo22b2o5b2o20bob5o3bobo$97bo6bo17b5ob3o3bo3bo$68bo3bo48bo4bo
5bo5b2o$63b2ob2ob3ob2ob2o42b2obo2b2o7bo$62bobobo7bobobo42bo4b2obo5b5o$
61b2obob2ob3ob2obob2o41bo3b3obo2b2o4b2o$61b3obo2bobobo2bob3o42b3o5bob
3o$68bobobo$63bo13bo47b3o5b2o$63b2o11b2o47b2o2bobob2o$62b3o11b3o49bobo
3bo$59bob2o15b2obo45b2obobo2bo$59bo2bo15bo2bo41b2o2b2obo3bob2o$59b2ob
2o13b2ob2o40bob2o2bob2ob2ob2o$59bo2bo15bo2bo40b3o2b2obo4b2obo$62bob2o
9b2obo47bo5b2ob2obo$60bobobob2o5b2obobobo44b2obo3bo3bo$59b2obobo3bo3bo
3bobob2o43b2obo4bo2b2o$62b5obo3bob5o50bo$59b2ob2ob2ob2ob2ob2ob2ob2o$
65bobo5bobo$60bo3bo11bo3bo$59bo4b2ob2o3b2ob2o4bo$60bo3b2ob2o3b2ob2o3bo
$59bobo3bobo5bobo3bobo$63b2o11b2o$59b2o19b2o2$60bo19bo$60bo19bo$59bobo
17bobo$59bo21bo11$5bo29bo29bo29bo29bo29bo29bo29bo29bo$4bobo7b3o17bobo
7b3o17bobo7b3o17bobo7b3o17bobo7b3o17bobo7b3o17bobo7b3o17bobo7b3o17bobo
7b3o$7bo2b2obo2bo20bo2b2obo2bo20bo2b2obo2bo20bo2b2obo2bo20bo2b2obo2bo
20bo2b2obo2bo20bo2b2obo2bo20bo2b2obo2bo20bo2b2obo2bo$2bo2bobobobobobob
o14bo2bobobobobobobo14bo2bobobobobobobo14bo2bobobobobobobo14bo2bobobob
obobobo14bo2bobobobobobobo14bo2bobobobobobobo14bo2bobobobobobobo14bo2b
obobobobobobo$bo2bo2bobo3bobob2o12bo2bo2bobo3bobob2o12bo2bo2bobo3bobob
2o12bo2bo2bobo3bobob2o12bo2bo2bobo3bobob2o12bo2bo2bobo3bobob2o12bo2bo
2bobo3bobob2o12bo2bo2bobo3bobob2o12bo2bo2bobo3bobob2o$2bo2bobobobobo2b
3o13bo2bobobobobo2b3o13bo2bobobobobo2b3o13bo2bobobobobo2b3o13bo2bobobo
bobo2b3o13bo2bobobobobo2b3o13bo2bobobobobo2b3o13bo2bobobobobo2b3o13bo
2bobobobobo2b3o$2bo4b3o3b2o17bo4b3o3b2o17bo4b3o3b2o17bo4b3o3b2o17bo4b
3o3b2o17bo4b3o3b2o17bo4b3o3b2o17bo4b3o3b2o17bo4b3o3b2o$3bo3bobo3bo19bo
3bobo3bo19bo3bobo3bo19bo3bobo3bo19bo3bobo3bo19bo3bobo3bo19bo3bobo3bo
19bo3bobo3bo19bo3bobo3bo$4b3o3b2o3bo18b3o3b2o3bo18b3o3b2o3bo18b3o3b2o
3bo18b3o3b2o3bo18b3o3b2o3bo18b3o3b2o3bo18b3o3b2o3bo18b3o3b2o3bo$5b3o3b
o23b3o3bo23b3o3bo23b3o3bo23b3o3bo23b3o3bo23b3o3bo23b3o3bo23b3o3bo$3b2o
11b2o15b2o11b2o15b2o11b2o15b2o11b2o15b2o11b2o15b2o11b2o15b2o11b2o15b2o
11b2o15b2o11b2o$2b2o6bob4o2bo13b2o6bob4o2bo13b2o6bob4o2bo13b2o6bob4o2b
o13b2o6bob4o2bo13b2o6bob4o2bo13b2o6bob4o2bo13b2o6bob4o2bo13b2o6bob4o2b
o$2bobo3bobo4bo16bobo3bobo4bo16bobo3bobo4bo16bobo3bobo4bo16bobo3bobo4b
o16bobo3bobo4bo16bobo3bobo4bo16bobo3bobo4bo16bobo3bobo4bo$bobobobobob
3o3bo2bo10bobobobobob3o3bo2bo10bobobobobob3o3bo2bo10bobobobobob3o3bo2b
o10bobobobobob3o3bo2bo10bobobobobob3o3bo2bo10bobobobobob3o3bo2bo10bobo
bobobob3o3bo2bo10bobobobobob3o3bo2bo$b3ob3obobob5ob2o10b3ob3obobob5ob
2o10b3ob3obobob5ob2o10b3ob3obobob5ob2o10b3ob3obobob5ob2o10b3ob3obobob
5ob2o10b3ob3obobob5ob2o10b3ob3obobob5ob2o10b3ob3obobob5ob2o$o3b2o3bo3b
o3b2o11bo3b2o3bo3bo3b2o11bo3b2o3bo3bo3b2o11bo3b2o3bo3bo3b2o11bo3b2o3bo
3bo3b2o11bo3b2o3bo3bo3b2o11bo3b2o3bo3bo3b2o11bo3b2o3bo3bo3b2o11bo3b2o
3bo3bo3b2o$8b2ob4o23b2ob4o23b2ob4o23b2ob4o23b2ob4o23b2ob4o23b2ob4o23b
2ob4o23b2ob4o$b2o5b4o3b2o14b2o5b4o3b2o14b2o5b4o3b2o14b2o5b4o3b2o14b2o
5b4o3b2o14b2o5b4o3b2o14b2o5b4o3b2o14b2o5b4o3b2o14b2o5b4o3b2o$11bo4bobo
22bo4bobo22bo4bobo22bo4bobo22bo4bobo22bo4bobo22bo4bobo22bo4bobo22bo4bo
bo$2b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o28b2o$3bo12bobo14bo12bobo14b
o12bobo14bo12bobo14bo12bobo14bo12bobo14bo12bobo14bo12bobo14bo12bobo$bo
3bo9b3o13bo3bo9b3o13bo3bo9b3o13bo3bo9b3o13bo3bo9b3o13bo3bo9b3o13bo3bo
9b3o13bo3bo9b3o13bo3bo9b3o$o5bo11b2o10bo5bo11b2o10bo5bo11b2o10bo5bo11b
2o10bo5bo11b2o10bo5bo11b2o10bo5bo11b2o10bo5bo11b2o10bo5bo11b2o$o5bo6bo
b2o2b2o9bo5bo6bob2o2b2o9bo5bo6bob2o2b2o9bo5bo6bob2o2b2o9bo5bo6bob2o2b
2o9bo5bo6bob2o2b2o9bo5bo6bob2o2b2o9bo5bo6bob2o2b2o9bo5bo6bob2o2b2o$2bo
2b2o6bobo3b2o11bo2b2o6bobo3b2o11bo2b2o6bobo3b2o11bo2b2o6bobo3b2o11bo2b
2o6bobo3b2o11bo2b2o6bobo3b2o11bo2b2o6bobo3b2o11bo2b2o6bobo3b2o11bo2b2o
6bobo3b2o$4b2o4bob4o18b2o4bob4o18b2o4bob4o18b2o4bob4o18b2o4bob4o18b2o
4bob4o18b2o4bob4o18b2o4bob4o18b2o4bob4o$9bobob2obo22bobob2obo22bobob2o
bo22bobob2obo22bobob2obo22bobob2obo22bobob2obo22bobob2obo22bobob2obo$
8b2o5bo22b2o5bo22b2o5bo22b2o5bo22b2o5bo22b2o5bo22b2o5bo22b2o5bo22b2o5b
o$8bob4o24bob4o24bob4o24bob4o24bob4o24bob4o24bob4o24bob4o24bob4o$7b3o
27b3o27b3o27b3o27b3o27b3o27b3o27b3o27b3o$7b2obo26b2obo26b2obo26b2obo
26b2obo26b2obo26b2obo26b2obo26b2obo$8bob2o26bob2o26bob2o26bob2o26bob2o
26bob2o26bob2o26bob2o26bob2o$9bo2bo26bo2bo26bo2bo26bo2bo26bo2bo26bo2bo
26bo2bo26bo2bo26bo2bo$10bo29bo29bo29bo29bo29bo29bo29bo29bo$6b2o5bo22b
2o5bo22b2o5bo22b2o5bo22b2o5bo22b2o5bo22b2o5bo22b2o5bo22b2o5bo$5bob2o3b
3o20bob2o3b3o20bob2o3b3o20bob2o3b3o20bob2o3b3o20bob2o3b3o20bob2o3b3o
20bob2o3b3o20bob2o3b3o$8b5obo23b5obo23b5obo23b5obo23b5obo23b5obo23b5ob
o23b5obo23b5obo$11bobo27bobo27bobo27bobo27bobo27bobo27bobo27bobo27bobo
$9bo3bo25bo3bo25bo3bo25bo3bo25bo3bo25bo3bo25bo3bo25bo3bo25bo3bo$6b2obo
b2o23b2obob2o23b2obob2o23b2obob2o23b2obob2o23b2obob2o23b2obob2o23b2obo
b2o23b2obob2o$9bobo27bobo25bobobob3o23bobo27bobo27bobo27bobo27bobo27bo
bo$8b2obo26b2obo26b2obob3o22b2obo26b2obo26b2obo26b2obo26b2obo26b2obo$
9bob2o26bob2o20b3o5b2obobo22bob2o26bob2o26bob2o26bobob2o24bobob2o24bob
ob2o$8b2o28b2o26b6o3b2o21b2o28b2o28b2o26b2obobob2o21b2obobob2o21b2obob
ob2o$10bobo27bobo20b3ob3o4bo25bobo27bobo27bobo23b2obobo24b2obobo24b2ob
obo$9b2ob2o25b2ob2o29b2obo22b2ob2o25b2ob2o25b2ob2o25bobob2o24bobob2o
24bobob2o$12bo24bo2bobo24b5o4bo25bo29bo29bo26bobob2o24bobob2o21b2obobo
b2o$7b2obo26bo2bo25b2o5bobo21b2obo26b2obo26b2obo28bobo27bobobo27bo$8b
3o3bo23bobo57b3o3bo23b3o3bo23b3o3bo22bobob2o23b2obobobo22b2o2b2o$9b3ob
o25b2obo23b2o3bo2bo24b3obo25b3obo25b3obo25b2o25bob3o2bobo26bo$11b2o22b
4obobob2o20bo4b2obo26b2o28b2o28b2o25bobo23bo2bo2b3o2b2o21b2o$10b3o25bo
3bob2o23b3o28b3o27b3o27b3o23bo3bo3bo18bo9bobo22bobobo$11bo24bo2bobo2b
2o21bo5bo27bo29bo29bo23b2o3b2o2b2o18b3o3b2o23b2o3bobob2o$35bo9bo21bo5b
2o110bo3b3obob2o18b3obo6bo17b2o3b4o3b2o$34bo10b2o20bob2ob2o113b2o2bob
2o25b2o22bo5bob2o2b2o$9b3o21bobo10b2o21b2ob2o25b3o27b3o27b3o28bo2b2o
24b3o2bo21bo2bobo4b2o$8b2ob2o22b2o31bobobo27bo29bo24b3ob3ob3o24b3o24b
2o2bo24b2obobo3b2o$6b2o5b2o19bobo7bo21b2o4b2o53b2o3b2o20bo11bo23b3o24b
o3bo21b2obo5bo2bo$7bo5bo21b3o6b2o19b3obo3bobo21b3ob3o23b2o3b2o21bob2o
3b2obo21bo4b2o23bo5bo19b2obo3bobobob2o$6bo7bo19bo2bo6b2obo16b2o5b2o2b
3o18b4ob4o23b5o26bobo24b2o5bo25bo24bobobobo3bo$7bo5bo21b2o10bo17bo5bo
5bo17bo2bo3bo2bo24bo24b2o7b2o19b2o2b2o3bo23bobo2bo20bobo2bob2o$44b2o
23b2o3bo20b3o5b3o24bo23bo3bo3bo3bo18b2o2b2ob2o22b3obobobo20bobo4bo3b2o
$64bo2b4o3bobo20b3ob3o25b3o25bo5bo22b2obo25b2obobobob3o18bo5bo2bob2o$
64bobo2b2o4bo22bo3bo24bo5bo21bo9bo20b2obob2o21bo2bo3b2o3bo16bobo2b6o$
99bobo24bo2bobo2bo22bo5bo25bobo22b3o5b3ob2o16bobob2o$98bo3bo23bo7bo54b
obo33b3o$99bobo26bo3bo23b2o5b2o24bob2o24bo31b2ob2o$98b2ob2o23b2o5b2o
53b2o24bo2b2o29bo$98b2ob2o53b3o3b3o25b3o25bo2b3o25b2obo$156bo7bo25bobo
23bobo4b3o22bobo$157bo5bo22bo3bobo22b2o35b2o$187bo4b2o22b2o6b2o20b2o2b
o3bo$188b3ob2o22b2o27b2o3b2o2bo$191bobo23bo5b3o19b2o3b2obo$192bo22b4o
3bob2o23b2o3bo$191bo22b2o3bobo24bob2o4b3o$188bob2o21bo5bobobo2bo20bo$
189b2o22bo5bo2bobobo20bo4bo$190bo22bo3bobo26bo3bob2o$189b3o21bo3bobo4b
o22b2o2b2obo$187bo5bo19bo4b2o5b2o23b2obo$186bo2bobo2bo18bo2bo7b2o24b2o
$186bo7bo19bo2bo30bo2bo$188bo3bo21bo2bo4bo24bobobo$186b2o5b2o22b2o3b2o
22b2obobob2o$215b2ob2obo2b2o20b2obob3o$214b2o3bobo2bobo19bo8bo$215bobo
bobobo23b3o5bo$213b5obobob5o19bobo5bo$213b3o3bobob2ob2o18b2o4b2o$214bo
7bo23b2o5bo$218bo7b2o18b2o5b2o$219b4o27bob3o$217b2o4bo26b2obo$216bo2bo
bo2bo22bobo$215b2ob3obobo21b3obo2bo$215b2o3bo2bo22bo2bo4bo$215b4o6bo
20bo2b2ob2o$214bob3o3bo2b3o19bo5bo$213bo2bo2b2o24b4o4bob2o$214bo2bo2b
2o3b3o17b4o3bob3o$216b2ob2o3b3o17bo4b4o$216bo4b2obo21b2o$214bob2obobob
ob2o18b2o3bo2bo$213bo2bo3b4o2bo23b2obobo$214bo5b4obo27b2o$220b3obo21b
2o3b2o$220b2o24b3o3bo$247bo2b2ob2o$247b3obo$246bo2bobob2o$245bo3bobo2b
o$245bo3bobo$246b5o4b2o$249bo3bobo$247b2o4b2o$247b2o4bo$246b2o$253b2o!
```

I have made several updates to knight2 and will be posting updated code on the knight2 thread on the scripts page in the next few days.

One thing that I have noticed in doing these higher period searches is that increasing the search width is providing very little benefit or encouragement in finding spaceships. This was particularly noticeable in the period 8 and period 10 searches that I did.

Have a happy day,

-Tim Coe

### Re: Spaceship Discussion Thread

Posted: **February 20th, 2016, 10:00 pm**

by **Sphenocorona**

calcyman wrote:Wait -- I can see how to get any speed strictly less than c/2 (by l_1 metric), but how do you handle the equality case? In particular, I don't think you've proved that there exists a (2, 1)c/6 spaceship.

I made a mistake, the equality shouldn't be there. And it probably isn't even true, since none of those velocities with velocity (x,y)c/2(x+y) are achievable by a ship that moves itself by universal construction, and the problem of determining if a spaceship exists at that velocity for any arbitrary choice of x and y is probably undecidable.

### Re: Spaceship Discussion Thread

Posted: **February 21st, 2016, 2:37 pm**

by **velcrorex**

A medium sized c/5 orthogonal I hadn't seen before. Not terribly interesting?

Code: Select all

```
x = 47, y = 20, rule = B3/S23
4b2o$ob2obo3bo$2o7b2o$2bob2o5bo$b2o2b2o3b3o7bo$5b2o4b2o6bobo$8b3obo6bo
2b2o$8b2o3bob3o4bo$9b3o4b2o4bo2b3o2b2o$12b5o6bo4bo2b2o$13b2o11bo$26bob
obo6bobo$30b2o3bo3b2o$27bo3bo3bo2bo$26b2o2bo3b2o6b3o$32bobo4b2ob4o$31b
2o2bo2bob2o4bo$34bo3bo7bo$42bo$43bo!
```

I know people were keeping track of small c/4 ships, any similar work on c/5?

### Re: Spaceship Discussion Thread

Posted: **February 21st, 2016, 3:19 pm**

by **muzik**

velcrorex wrote:A medium sized c/5 orthogonal I hadn't seen before. Not terribly interesting?

Code: Select all

```
x = 47, y = 20, rule = B3/S23
4b2o$ob2obo3bo$2o7b2o$2bob2o5bo$b2o2b2o3b3o7bo$5b2o4b2o6bobo$8b3obo6bo
2b2o$8b2o3bob3o4bo$9b3o4b2o4bo2b3o2b2o$12b5o6bo4bo2b2o$13b2o11bo$26bob
obo6bobo$30b2o3bo3b2o$27bo3bo3bo2bo$26b2o2bo3b2o6b3o$32bobo4b2ob4o$31b
2o2bo2bob2o4bo$34bo3bo7bo$42bo$43bo!
```

I know people were keeping track of small c/4 ships, any similar work on c/5?

I'm not entirely sure, but that kind of resembles two spaceships fused together.