Simplest 2 gliders in/1 glider out 180° stable reflector?

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pcallahan
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Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by pcallahan » June 2nd, 2021, 2:09 pm

There may be an existing thread to cover this, but I was unable to find it. I am curious if anyone has done a search for the pattern described in the subject line. Here's the basic idea:
  • Two gliders traveling in the same direction (not necessarily the same path) hit a stable constellation.
  • Both gliders are cleanly destroyed.
  • Another glider is sent in the opposite direction along a path that does not collide with either entering glider.
  • The object is fully restored and reusable at some point after the collision.
It seems like it should be easier to find a pattern like this than a stable reflector, and it could possibly be very small, though probably not as simple as a single block or it would have been noticed when searching for block pushers (as Dean Hickerson did a long time ago).

There are simply a lot more combinations to try of gliders entering at different relative phases, and some constellation of still lifes could restore itself, either alone or with the assistance of a catalyst. I just don't remember ever searching for such a pattern (since it seemed less interesting than a stable reflector) but I wonder if anyone else has.

Just as a strawman, here is one based on the initial stage of the first stable reflector. Two gliders enter so one can clean up the beehive (like the Herschel receiver, but adjusted to avoid the exiting glider). Instead of trying to perturb the result into a Herschel, I just want to eat it as long as the block is restored. In fact, the best I could find with gencols was one exiting glider in the original direction. So I have to add another eater to get rid of it*.

Code: Select all

x = 94, y = 94, rule = B3/S23
2bo$obo$b2o5$10bo$11b2o$10b2o41$52bo$50bobo$51b2o3$78bo$76b3o$60bo14bo
$61b2o12b2o$60b2o5$85bo$83b3o$82bo$70bo11b2o$60b2o7bobo$60b2o7bobo$70b
o5$72b2o$72b2o9$90b2o$90bobo$92bo$92b2o2$76b2o$77bo$74b3o$74bo!
So... it's pretty simple. Two blocks and four eaters (and a beehive if the cleanup glider goes first). There has to be something better though, right?

*The reason I want to remove the extra glider is that this is intended as the terminal of a glider memory loop. Pairs of gliders can be produced at low cost at one end, but I want the terminal to be as simple as possible. I also don't want any glider pollution. I couldn't find any simpler way just to eat the extra part, but I did not look very hard. This is just to illustrate what the pattern is supposed to do and my example is intentionally clunky.

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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by dvgrn » June 2nd, 2021, 3:12 pm

pcallahan wrote:
June 2nd, 2021, 2:09 pm
There are simply a lot more combinations to try of gliders entering at different relative phases, and some constellation of still lifes could restore itself, either alone or with the assistance of a catalyst. I just don't remember ever searching for such a pattern (since it seemed less interesting than a stable reflector) but I wonder if anyone else has.
There are quite a few known conduits with tandem-glider inputs, but interest in them has been waning recently. Well, not just recently, I guess, more like for the last decade. No matter how many such things we discover, nobody can really actually find a use for any of them. For most purposes, Snarks and syringes are just plain easier to work with.

There are several known semi-Snarks (2 gliders in/1 glider out) but they're all 90-degree reflectors, so arguably your old 1990s-era beehive stopper variant is still the best known solution to your problem. (!)

Here's another modification of the old tandem-glider receiver, with fewer eaters and more blocks. Might just possibly turn out to be cheaper to move.

Code: Select all

x = 70, y = 63, rule = LifeHistory
24.3D9.3D2.4D4.D6.D3.3D2.4D$23.D3.D7.D3.D.D3.D2.2D5.2D2.D5.D3.D$23.D
15.D.D3.D3.D4.D.D2.D5.D3.D$23.D2.2D.5D4.D2.4D4.D3.D2.D2.4D2.4D$23.D3.
D9.D3.D2.D4.D3.5D.D3.D.D2.D$23.D3.D8.D4.D3.D3.D6.D2.D3.D.D3.D$24.3D8.
5D.D3.D2.3D5.D3.3D2.D3.D5$28.4D3.3D2.D3.D2.3D2.5D4.D4.D$28.D3.D.D3.D.
D3.D.D3.D3.D5.2D3.2D$28.D3.D.D5.D3.D.D2.2D3.D4.D.D4.D$28.4D3.3D2.D.D.
D.D.D.D3.D3.D2.D4.D$28.D2.D6.D.D.D.D.2D2.D3.D3.5D3.D$28.D3.D.D3.D.2D.
2D.D3.D3.D6.D4.D$28.D3.D2.3D2.D3.D2.3D4.D6.D3.3D5$31.2A$30.B2AB$30.4B
$31.2B$29.2A3B$29.2A5B$16.2A11.8B$17.A6.2B5.6B$17.A.AB2.6B.9B$18.2AB.
B.17B$14.2A4.24B$13.B2AB2.27B$14.3B2.27B3.2A$13.B.B2.29B.B2AB$12.35B.
4B$12.34B.B.2B2.3B$10.33BD13B$10.29B2.2B2D12B$11.12B2C2B2A8B4.B2D13B$
10.12BCBC2B2A6B5.17B$11.13BC9B5.16B.B2A$13.B2.17B5.17B.BA.A$17.14B6.
13B.B.B5.A$16.14B6.4B3.7B9.2A$15.14B6.4B4.8B$14.13B7.4B6.7B$13.13B8.
3B10.4B$12.12B10.2B10.4B$11.6B3.B.B11.B10.B2A2B$10.6B3.3B24.2A$9.6B4.
B2AB$8.6B6.2A$7.6B$6.6B$5.6B$4.6B$3.6B$2.6B$.2C4B$CBC3B$.BC2B!
I'll mention one more option that might be interesting to try: I can reduce the still-life cost to just one eater, three blocks, and a loaf if I'm allowed to include a few extra gliders in the outgoing signal, and if you don't mind reducing you loop's storage density a little bit. This is a 6-glider tandem input, for example -- I was looking for the right equivalent word meaning "six", but it turns out that "tandem" really means "two or more" // "at length".

Code: Select all

x = 68, y = 116, rule = LifeHistory
2.A$A.A$.2A17$18.A$16.A.A$17.2A15$34.A$32.A.A$33.2A8$49.A$50.2A$49.2A
31$25.4B4.A$26.4B4.A$27.4B.3AB$28.4B.4B$29.4B.4B29.B$30.4B.4B27.2B$
31.4B.4B25.3B$32.4B.4B23.4B$33.4B.4B21.4B$34.4B.4B19.4B$35.4B.4B17.4B
$36.4B.4B15.4B$37.4B.4B13.4B$38.4B.4B11.4B$39.4B.4B9.4B$40.4B.4B7.4B$
41.4B.4B5.4B$42.4B.4B3.4B$43.4B.4B.4B$44.4B.7B5.2A$45.4B.6B5.A$46.3BA
4BA2B.BA.A$47.3BA2BABAB.B2A$45.2B.3ABA2BA3B$44.2A7B2A4B$44.2A13B$45.
2B2.10B$49.12B.B$50.12B2A$50.12B2A$50.9B.3B$51.6B4.B$52.4B$53.2B$52.
2B$51.B2AB$52.2A!
... I have to say, I don't really think this is an improvement, but maybe it will give somebody else a better idea.

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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by MathAndCode » June 2nd, 2021, 3:22 pm

pcallahan wrote:
June 2nd, 2021, 2:09 pm
Just as a strawman, here is one based on the initial stage of the first stable reflector. Two gliders enter so one can clean up the beehive (like the Herschel receiver, but adjusted to avoid the exiting glider). Instead of trying to perturb the result into a Herschel, I just want to eat it as long as the block is restored. In fact, the best I could find with gencols was one exiting glider in the original direction. So I have to add another eater to get rid of it*.

Code: Select all

x = 94, y = 94, rule = B3/S23
2bo$obo$b2o5$10bo$11b2o$10b2o41$52bo$50bobo$51b2o3$78bo$76b3o$60bo14bo
$61b2o12b2o$60b2o5$85bo$83b3o$82bo$70bo11b2o$60b2o7bobo$60b2o7bobo$70b
o5$72b2o$72b2o9$90b2o$90bobo$92bo$92b2o2$76b2o$77bo$74b3o$74bo!
So... it's pretty simple. Two blocks and four eaters (and a beehive if the cleanup glider goes first). There has to be something better though, right?
I managed to find this version, which is worse by catalyst number and population but is probably better in terms of slow-salvo constructability (although I'm not completely sure):

Code: Select all

x = 28, y = 39, rule = LifeHistory
18.A$16.3A$15.A$15.2A2$2.A$3.A$.3A2$25.A$23.3A$22.A$22.2A$2A$2A6$12.2A
$12.2A6$26.2A$26.2A5$26.2A$26.2A$18.A$16.3A$15.A$15.2A!
This reminds me that I've been wondering for a while about the possibility of assigning slow-salvo-expensiveness scores to objects in order to have a quick way of estimating which conduit or version of a conduit would be cheaper/quicker to construct with a slow slavo. Is this something that others have already done work on?



Edit: I kept looking and found this:

Code: Select all

x = 30, y = 36, rule = B3/S23
18bo$16b3o$15bo$15b2o2$2bo$3bo$b3o2$25bo$23b3o$22bo$22b2o$2o$2o6$12b2o
$12b2o5$28b2o$28b2o5$14b2o$13bobo$13bo$12b2o!


Another edit: I found a version with two blocks.

Code: Select all

x = 30, y = 38, rule = B3/S23
18bo$16b3o$15bo$15b2o2$2bo$3bo$b3o2$25bo$23b3o$22bo$22b2o$2o$2o6$12b2o
$12b2o5$28b2o$28b2o9$18b2o$18b2o!
I am tentatively considering myself back.

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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by pcallahan » June 2nd, 2021, 3:53 pm

dvgrn wrote:
June 2nd, 2021, 3:12 pm
There are quite a few known conduits with tandem-glider inputs, but interest in them has been waning recently. Well, not just recently, I guess, more like for the last decade. No matter how many such things we discover, nobody can really actually find a use for any of them.
Well, whether they're useful or not, I wonder how much is known about fast tandem pairs.

The search for true reflectors limits the search space to still life arrangements. I already have a sense of how hard it is to find useful reactions in that space, but suppose you started with glider pairs phased apart by anywhere from 14 to 100 generations and up to 10 diagonals apart. That will provide a much larger multiplier. Collide those pairs with blocks and see if a second block or eater can perturb the result to restore the block and release a glider. Can we rule out the existence of a reflector like that using only a block and an eater? It doesn't seem like a such a hard search even with the primitive tools I was using 25 years ago. I don't think I ever generated tandem pairs like that (gencols can't do it because they never collide). I may look at this if it hasn't been done.

And as you might have guessed, I am still thinking about an extensible bit loop without the massive waste of a puffer. Using two snarks as the terminal will clearly work, but something simpler would be nice even at the cost of doubling the count of forward gliders. (Though I realize that asymptotically, the snark pair instructions have a constant cost and will eventually be more "economical".)
Last edited by pcallahan on June 2nd, 2021, 4:09 pm, edited 2 times in total.

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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by pcallahan » June 2nd, 2021, 3:57 pm

pcallahan wrote:
June 2nd, 2021, 3:53 pm
Another edit: I found a version with two blocks.
Nice! I was hoping to find something like that to post as an example but I gave up. However, I still think there must be something a lot simpler if we include the glider pair spacing and phase shift in the search.

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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by Kazyan » June 2nd, 2021, 4:23 pm

To be clear, are the two input gliders allowed to require exact-timing? The examples posted so far allow the gliders to have arbitrary timing.
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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by pcallahan » June 2nd, 2021, 4:43 pm

Kazyan wrote:
June 2nd, 2021, 4:23 pm
To be clear, are the two input gliders allowed to require exact-timing? The examples posted so far allow the gliders to have arbitrary timing.
Yes, they are, though my examples did not. That's why I'm optimistic there could be something very simple that works.

In fact, using a Python script to generate pairs and gencols to collide with a block, I just found this messy and presumably useless block restoration.

Code: Select all

x = 23, y = 21, rule = B3/S23
bo$2bo$3o9$10bo$11b2o$10b2o6$21b2o$21b2o!
If the search had included a catalyst as well, could we find something that restores the block and cleanly emits a glider?

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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by Kazyan » June 2nd, 2021, 4:51 pm

I'm certain that a two-object solution exists, in that case. I'll see what CatForce can come up with using only Spartan objects.
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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by dvgrn » June 2nd, 2021, 5:55 pm

pcallahan wrote:
June 2nd, 2021, 3:53 pm
I don't think I ever generated tandem pairs like that (gencols can't do it because they never collide). I may look at this if it hasn't been done.
Unless I'm forgetting something, the last investigation along these lines was by chris_c (Chris Cain) in 2015, and that was again an investigation looking for 90-degree gliders.

Probably it would be better to have a total newcomer run the CatForce search, instead of Kazyan. Just need someone with enough beginner's luck to find really impressive things that weren't there before, like the loafer and the copperhead and the two-engine Cordership.

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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by pcallahan » June 2nd, 2021, 6:23 pm

dvgrn wrote:
June 2nd, 2021, 5:55 pm
Unless I'm forgetting something, the last investigation along these lines was by chris_c (Chris Cain) in 2015, and that was again an investigation looking for 90-degree gliders.
So I guess 3 gliders hitting a block is reasonable, unless there is something intrinsically harder about 180°. Keeping the paths clear could be an issue. If there was also a way to push the block farther out cleanly on the same diagonal, it would satisfy the minimal requirements of an extensible memory. Maybe that has already been done with somewhat more gliders, though I don't think any of Dean Hickerson's sliding block constructions produce backward gliders that can pass the forward gliders.

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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by Entity Valkyrie 2 » June 2nd, 2021, 7:13 pm

The boojum happens to be Spartan.

Code: Select all

x = 45, y = 32, rule = B3/S23
4bobo6b2o$5b2o6b2o$5bo7$40bo$39bobo$39bobo$20b2o16b2ob3o$20b2o22bo$38b
2ob3o$2b2o34b2obo$bobo$bo$2o2$34b2o$34b2o4b2o$11b2o27bobo$10bobo29bo$
10bo31b2o$9b2o23b2o$34b2o3$29bo$28bobo$29bo!
It also works for a pair of gliders.

Code: Select all

x = 70, y = 59, rule = B3/S23
obo$b2o$bo25$29bobo6b2o$30b2o6b2o$30bo7$65bo$64bobo$64bobo$45b2o16b2ob
3o$45b2o22bo$63b2ob3o$27b2o34b2obo$26bobo$26bo$25b2o2$59b2o$59b2o4b2o$
36b2o27bobo$35bobo29bo$35bo31b2o$34b2o23b2o$59b2o3$54bo$53bobo$54bo!
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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by pcallahan » June 2nd, 2021, 7:22 pm

Entity Valkyrie 2 wrote:
June 2nd, 2021, 7:13 pm
The boojum happens to be Spartan.
A boojum would be an option for terminating a single-glider extensible memory loop, though I have no idea how it compares to two snarks in terms of construction cost. I'm looking for something much cheaper on the assumption that I'm willing to use 2 outbound gliders (with exact timing) for each 1 bit.

The ideal solution would be something that's relatively simple to push farther out rather than have to erase and construct. This is admittedly an ill-defined distinction, but I mean in the sense that it is a component in its own synthesis, but displaced along a diagonal, i.e. like Dean Hickerson's block pusher from 1991. This is pretty close to what I want, but the gliders cannot pass each other (also, most of the time, I want it to reflect without pushing). I would still rather keep the glider count down to 2, or at least I'm curious if that's possible. Maybe if the reflector end consisted of two blocks, it would be simple enough to find a reasonable pusher for it (I realize that pushing can be done using more advanced construction methods, but I am thinking of something pretty quick with just a few gliders with exact timing allowed).

Code: Select all

#N Block pusher 5
#C Population is bounded, but some cells never become periodic.
#C A 3 glider salvo pushes a block 10 units southeast and sends back
#C 2 gliders, which cause another salvo to be fired.  The round trip
#C time increases by an average of 80 generations each time.  More
#C specifically, for n>=0, a salvo hits the block in generation
#C 40 n^2 + 760 n + a[n mod 3],  where a[0]=426, and a[1]=a[2]=626.
#O Dean Hickerson, dean.hickerson@yahoo.com  4/16/1991
x = 137, y = 145, rule = B3/S23
40b2o$38bo2bo$37bo$37bo$27b2o8bo$15b2o9bo2b3o6bo2bo2b2o3b4o16b2o$15bo
11b2o11b2o2bo4b2o2bo14bo$49b4o14bo$58bo8bo9b2o$57bo9bo9bo$57b3o8bo$69b
2o$34b2o$34bo$32bobo$32b2o$27bo39b2o$9bo16b5o37bo$7b3o17bob2o37bobo$2o
5bo2bo22b2o34b2o8bo$o6b3o23bo45b3o$9bo68bo2bo7b2o$33bo2bo42b3o7bobo3bo
$23b2o7bo2bo32b2o9bo10b2ob2o6b2o$5b2o16bo8bobo34bo24b2o5bo$5bo27bo17b
2o$47b4o4b2o9bo2bo$33b2o12b3ob2o2bo11bo2bo$33bo18bo15bobo6b2o$69bo7bo$
6bo37b2o$6bobo36bo22b2o$6b2o37bobo20bo$46b2o$58b2o5b2o$6b2o46b2o2bobo
4bo$6bobo44bobo2bo20b2o11b2o10b2o$7b2o44b2o24bo2bo6b3o2bo9bo$19bo63bo
8b2o$19b3o61bo$22bo60bo$21b2o49b2o5bo2bo$71bobo5b2o$71bo$70b2o$47b2o$
47bo$5b2o3b2o9bo5bo$5bo5bo9bo5bo$22bo3bo$6bo3bo12b3o90b2o$7b3o84bo21bo
$74bo18bobo18bobo$72b3o7b2o12b2o6b2o8b2o$71bo10bo10b3o8bobo2bo$71b2o
32b2o2bobo$109b2o2$8b2o104b2o$8bo14b2o89bo$23bo46bo$68bobo56b2o$34bo
34b2o56bo$34b3o31b2o$15bo2bo18bo30b2o$10b2o2b2o3bo16b2o29bobo$10bo8bo
47b2o42bo5bo10bo$5b2o8b4o92bo5bo10bo$5bo106bo3bo11bo$113b3o11bobo$28bo
98bobo$26b3o42b2o55bo$25bo45bo$25b2o45b3o$38bobo33bo$38bo2bo$38bobo$
39bo5b2o$20bo5bo12bo4bobo81bo$4b3o13bo5bo17bo67bo14bo$4bobo14bo3bo17b
2o66b3o13b3o$22b3o4bo81b3o$5bo23b3o$4bobo25bo6b2o68b2o3b2o$31b2o6bo69b
o5bo11b2o3b2o$127bo5bo$6b3o$6b3o119bo3bo$5bo3bo119b3o$4bo5bo$5bo3bo99b
2o$6b3o13bo87bo$21b3o10bo72b3o$22b2o9bobo71bo$33bobo96b3o$20bo12b3o96b
3o$18b2obo11b3o95bo3bo$19b2o109bo5bo$131bo3bo$132b3o$31b2o83bo$7b2o23b
o79b2o2b2ob3o$7bo21b3o45b2o33bo5b4o$29bo46bobo37b2o$20b2o56bo$20bo$54b
2o$54bo$39bo58bo$38b2obo55bo$27b2o9bo3bo54b3o32bo$27bo10b2obo88bobo$
39bo6b2o7bo75b2o$46bobo6bobo72b2o$48bo6b2o73b2o$48b2o79bobo$129b2o$55b
2o49b2o$55bobo48bo$56b2o2$133b2o$133bo$134b3o$136bo$52b2o$53bo$50b3o$
50bo5$67bo$66b2o$66bobo2$60b2o$60bob2obo$52b2o7b4o$52bo11b3o$71b2o$71b
obo$73bo$73b2o!

Null

Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by Null » June 3rd, 2021, 9:43 am


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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by dvgrn » June 3rd, 2021, 9:47 am

Null wrote:
June 3rd, 2021, 9:43 am
Would this help
2G-to-DIY

https://www.conwaylife.com/forums/viewt ... 814#p58814
Probably not, partly because it would be necessary to shoot down and re-construct that awkwardly large catalyst to increase the loop size. It seems like it's definitely going to be cheaper to stick with Spartan-ish stuff for this particular application.

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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by pcallahan » June 3rd, 2021, 11:19 am

dvgrn wrote:
June 3rd, 2021, 9:47 am
It seems like it's definitely going to be cheaper to stick with Spartan-ish stuff for this particular application.
Maybe just to set a precise bound on the kind of solution that I'd be happy to see: it should consist of still lifes with a total cell count of 11 or less, and no single still life with more than 7 cells. A block and eater is the obvious target, but there may be other solutions within those constraints. (So yeah, Spartan-ish.)

There should still be two gliders in, one glider out at 180° on a non-conflicting path. The self-repair should be clean (no excess gliders), but it doesn't have to be very fast.

A 90° reflector like that would also be a little bit interesting I think but not as easy to turn into the movable end of bit memory loop.

For that matter, I wonder if it helps to permit period-2, allowing blinkers and toads. This would make the timing a little less general for use as a memory loop but that seems like a problem that can be handled easily at the control end.

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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by Kazyan » June 3rd, 2021, 11:47 am

pcallahan wrote:
June 3rd, 2021, 11:19 am
Maybe just to set a precise bound on the kind of solution that I'd be happy to see: it should consist of still lifes with a total cell count of 11 or less, and no single still life with more than 7 cells. A block and eater is the obvious target, but there may be other solutions within those constraints. (So yeah, Spartan-ish.)

There should still be two gliders in, one glider out at 180° on a non-conflicting path. The self-repair should be clean (no excess gliders), but it doesn't have to be very fast.

A 90° reflector like that would also be a little bit interesting I think but not as easy to turn into the movable end of bit memory loop.

For that matter, I wonder if it helps to permit period-2, allowing blinkers and toads. This would make the timing a little less general for use as a memory loop but that seems like a problem that can be handled easily at the control end.
There's a cheap-ish Herschel receiver that could feasibly be adapted, albeit not within the 11-cell limit:

Code: Select all

x = 25, y = 17, rule = B3/S23
23bo$21b3o$5b2o13bo$5b2o13b2o4$bo$bo$bo21b2o$23b2o$7bo$6bobo$6bobo$7b
o2b3o$10bo$11bo!
Tanner Jacobi
Coldlander, a novel, available in paperback and as an ebook. Now on Amazon.

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pcallahan
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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by pcallahan » June 3rd, 2021, 12:34 pm

pcallahan wrote:
June 3rd, 2021, 11:19 am
For that matter, I wonder if it helps to permit period-2, allowing blinkers and toads. This would make the timing a little less general for use as a memory loop but that seems like a problem that can be handled easily at the control end.
To follow up on that idea, here is a collision between two gliders and a blinker that restores the blinker and creates a new one. If it just produced a glider instead I'd be done (yeah, I've heard that before).

Code: Select all

x = 22, y = 18, rule = B3/S23
bo$2bo$3o6$10bobo$11b2o$11bo7$19b3o!

Null

Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by Null » June 3rd, 2021, 6:24 pm

I knew I've seen something on this topic!
viewtopic.php?f=2&t=1599&p=20210#p20210
You are welcome :)

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pcallahan
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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by pcallahan » June 3rd, 2021, 6:37 pm

Null wrote:
June 3rd, 2021, 6:24 pm
I knew I've seen something on this topic!
viewtopic.php?f=2&t=1599&p=20210#p20210
You are welcome :)
Thanks. This one is good but it does not leave clearance for the return glider. I'm starting to think this will rule out a lot of possibilities.

Code: Select all

x = 28, y = 22, rule = B3/S23
12bo$11bobo$12bo4$11b2o$11b2o2$2o$2o5$15b3o$15bo$16bo2$26bo$25b2o$25bo
bo!

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Kazyan
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Re: Simplest 2 gliders in/1 glider out 180° stable reflector?

Post by Kazyan » June 3rd, 2021, 7:18 pm

There may be something involving this beehive-and-eater edgeshooter:

Code: Select all

x = 17, y = 15, rule = LifeHistory
2A13.A$2A12.A.A$14.A.A$10.3A2.A$12.A$11.A2$15.A$14.A.A$14.A.A$15.A$
10.2A$9.A.A$9.A$8.2A!
Tanner Jacobi
Coldlander, a novel, available in paperback and as an ebook. Now on Amazon.

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