# LifeWiki:Game of Life Status page

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## Contents

## Oscillator periods

For green status, an oscillator must have a cell that oscillates at the full period, rather than some smaller factor of that period. One such cell is sufficient.

Yellow means that the only known examples contain no cells that oscillate at the full period.

1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 |

13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 |

25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 |

37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 |

49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 60 |

61 | 62 | 63 | 64 | 65 | 66 | 67 | 68 | 69 | 70 | 71 | 72 |

All higher periods are known |

**Most recent discoveries:**

Apr 2013: p43 and p53 oscillators [Mike Playle]

Nov 2010: p31 oscillator [Matthias Merzenich]

Apr 2009: p37 oscillator [Nicolay Beluchenko]

Feb 2009: p51 oscillator [Nicolay Beluchenko]

Nov 2002: p27 oscillator [Noam Elkies]

Jul 2000: p39 oscillator [Noam Elkies with David Buckingham]

Aug 1999: p49 oscillator [Noam Elkies]

Dec 1997: p57 oscillator [Dieter Leithner with David Buckingham]

Jun 1997: p33 oscillator [Noam Elkies, Achim Flammenkamp]

27 Apr 1997: p17 oscillator [Dean Hickerson]

17 Apr 1997: p22 oscillator [Noam Elkies]. ([Dean Hickerson] found a second, unrelated, p22 oscillator a day or two later.)

11 Apr 1997: p59 oscillator [David Buckingham]

Oct 1996: Herschel track method of constructing any period 61 or
higher [David Buckingham]

## Glider reflectors

This table indicates whether a period-N glider stream can be reflected 90 degrees by an object whose period is N, or some factor of N.

This may seem to be a rather odd thing to keep track of, but 90-degree glider reflectors are very useful, and happen to be quite difficult to find in Life. Note that this table fits neatly between oscillators and guns -- if you have a gun, you can build a reflector, and if you have a reflector, you can build an oscillator.

Yellow means that the reflector requires the glider stream to have no gaps.

1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 |

13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 |

25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 |

37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 |

49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 60 |

61 | 62 | 63 | 64 | 65 | 66 | 67 | 68 | 69 | 70 | 71 | 72 |

All higher periods are known |

**Most recent discoveries:**

28 Aug 2013: p29 independent reflector [Matthias Merzenich]

25 Aug 2013: p29 dependent reflector [Matthias Merzenich]

May 2013: p20 [follows from p20 gun]

Apr 2013: Independent reflector for all periods 43 and over [Mike Playle].
Specifically: p43 and p53 (had nothing); p47 and p51 (had oscillators);
p57 and p61 (had dependent reflectors).

Sep 2012: p58 independent reflector [Matthias Merzenich]

Sep 2012: p52 reflector [Matthias Merzenich]

Feb 2012: p26 dependent reflector [Matthias Merzenich with Mike Playle]

Nov 2010: p31 reflector [Matthias Merzenich]

Mar 2010: p37 reflector [Nicolay Beluchenko]

Dec 2009: p59 reflector [follows from p59 gun]

## Glider gun true-periods

1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 |

13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 |

25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 |

37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 |

49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 60 |

61 | 62 | 63 | 64 | 65 | 66 | 67 | 68 | 69 | 70 | 71 | 72 |

All higher periods are known |

**Most recent discoveries:**

Apr 2016: p57 gun [Matthias Merzenich]

Apr 2016: p58 gun ['thunk', Matthias Merzenich with Chris Cain]

Apr 2016: p61 gun [Luka Okanishi]

May 2013: p20 gun [Matthias Merzenich with Noam Elkies]

Mar 2013: p40 gun [Matthias Merzenich with Jason Summers, Adam P. Goucher]

Apr 2010: p45 gun [Matthias Merzenich]

Dec 2009: p59 gun [Adam P. Goucher with Jason Summers]

Jul 2004: p36 gun [Jason Summers]

Aug 2000: p22 gun [David Eppstein, Jason Summers]

Oct 1998: p55 gun [Stephen Silver, Noam Elkies with David Buckingham]

29 Jan 1998: p56 gun [Dietrich Leithner, Noam Elkies with David Buckingham]

26 Jan 1998: p54 gun [Dietrich Leithner with David Buckingham, Noam Elkies]

Jun 1997: p24 gun, and related p48 gun [Noam Elkies]

13 Oct 1996: p50 gun [Dean Hickerson with Noam Elkies, David Buckingham]

12 Oct 1996: Herschel track method of constructing any period 62 or
higher [David Buckingham]

## Gun pseudo-periods

Glider | LWSS | MWSS | HWSS |
---|---|---|---|

All lower periods are impossible. | |||

13 | 13 | 13 | 13 |

14 | 14 | 14 | 14 |

15 | 15 | 15 | 15 |

16 | 16 | 16 | 16 |

17 | 17 | 17 | 17 |

18 | 18 | 18 | 18 |

19 | 19 | 19 | 19 |

20 | 20 | 20 | 20 |

21 | 21 | 21 | 21 |

22 | 22 | 22 | 22 |

23 | 23 | 23 | 23 |

All higher periods are known. |

Velocity is the combination of speed and slope (direction).

In this section, velocity is in the form (X,Y)c/P, where X>=Y, and no factor is common to all of X, Y, and P. (c is the "speed of light": 1 cell/generation.) P is therefore the minimum possible period for that velocity; X and Y are the (average) number of cells moved horizontally and vertically in P generations. The slope (direction) is Y/X, and the speed is Xc/P.

For example, (2,0)c/5 indicates movement of 2 cells horizontally and no cells vertically every 5 generations.

"Versatile puffer," means that for some period, we can build a clean glider rake with the gliders traveling in any of the possible directions.

Whether an object is a "wickstretcher" is to some extent a judgment call. For this table, the wick is required to be reasonably closely connected in all phases, and must in some sense be extended at a single location, rather than being built up slowly from pieces.

The "Gun?" column indicates whether a gun has been built which fires spaceships of that velocity. Yellow means that there is known glider synthesis for a spaceship, but no explicit example gun has been constructed yet.

Velocity | Spaceship? | Puffer? | Versatile puffer? | Wick- stretcher? | Gun? |
---|---|---|---|---|---|

(1,0)c/2 | Yes | Yes | Yes | Yes | Yes |

(1,0)c/3 | Yes | Yes | Yes | No | Yes |

(1,0)c/4 | Yes | Yes | Yes | Yes | No |

(1,1)c/4 | Yes | Yes | Yes | Yes | Yes |

(1,0)c/5 | Yes | Yes | Yes | Yes | No |

(2,0)c/5 | Yes | Yes | Yes | No | Yes |

(1,1)c/5 | Yes | Yes | Yes | Yes | No |

(1,0)c/6 | Yes | No | -- | No | No |

(2,1)c/6 | No | No | -- | No | -- |

(1,1)c/6 | Yes | No | -- | No | No |

(1,0)c/7 | Yes | Yes | Yes | No | Yes |

(2,0)c/7 | Yes | Yes | Yes | No | Yes |

(3,0)c/7 | Yes | Yes | No | No | No |

(2,1)c/7 | No | No | -- | No | -- |

(1,1)c/7 | Yes | No | -- | No | No |

(1,0)c/8 | Yes | Yes | Yes | No | No |

(3,0)c/8 | No | No | -- | No | -- |

(3,1)c/8 | No | No | -- | No | -- |

(2,1)c/8 | No | No | -- | No | -- |

(1,1)c/8 | No | No | -- | No | -- |

(1,0)c/10 | Yes | Yes | Yes | No | Yes |

(1,1)c/12 | Yes | Yes | Yes | Yes | Yes |

(17,0)c/45 | Yes | Yes | Yes | No | No |

(23,5)c/79 | Yes | Yes | Yes | No | No |

(31,0)c/240 | Yes | Yes | Yes | No | No |

Other |
Universal constructor-based spaceships (and other objects) that move very slowly have been made. The first such object has a velocity of (5120,1024)c/33699586. |

**Most recent discoveries (new velocities):**

Jun 2016: 3c/7 orthogonal spaceship [Tim Coe]

Apr 2016: c/8 orthogonal spaceship [Michael Simkin with David Bell, Alexey Nigin]

Mar 2016: c/10 orthogonal spaceship ['zdr']

Dec 2015: 13c/96228 (~ c/7402) diagonal 0hd Demonoid [Chris Cain, Dave Greene]

Nov 2015: c/12700 diagonal 10hd Demonoid [Dave Greene, Chris Cain]

Dec 2014: (23,5)c/79 spaceship [Brett Berger, Ivan Fomichev with Nicolay Beluchenko]

Sep 2014: 31c/240 orthogonal spaceship [Dave Greene, Ivan Fomichev, Adam P. Goucher, Chris Cain with Kiho Park]

Jul 2014: Half-baked knightships [Adam P. Goucher, Chris Cain, Ivan Fomichev, Dave Greene]

Feb 2013: c/7 orthogonal spaceship [Josh Ball]

Aug 2011: c/7 diagonal spaceship [Matthias Merzenich]

May 2010: Universal constructor-based "Gemini" spaceship [Andrew Wade]

Sep 2005: c/6 diagonal spaceship [Nicolay Beluchenko]

Dec 2004: 17c/45 orthogonal spaceship [Gabriel Nivasch, Jason Summers with David Bell]

Nov 2000: c/5 diagonal spaceship [Jason Summers; search software by David Bell]

Apr 2000: c/6 orthogonal spaceship [Paul Tooke; search software by David Eppstein]

Jan 2000: 2c/7 orthogonal spaceship [David Eppstein]

Jan 1996: c/5 orthogonal spaceship [Tim Coe]

**Most recent discoveries (other):**

Mar 2017: 3c/7 orthogonal puffer [Luka Okanishi]

Apr 2016: c/7 orthogonal (versatile) puffer [Michael Simkin with David Bell, Alexey Nigin]

Apr 2016: c/8 orthogonal (versatile) puffer [Michael Simkin with David Bell, Alexey Nigin]

Mar 2016: c/10 orthogonal (versatile) puffer [Nico Brown with Simon Ekström]

Mar 2016: c/10 orthogonal spaceship gun [Alexey Nigin with 'zdr']

Mar 2016: c/10 orthogonal spaceship synthesis [Tanner Jacobi with Mark Niemiec, Chris Cain]

Sep 2015: 2c/7 orthogonal spaceship gun [Chris Cain] (based on the 2c/7 spaceship synthesis from Jan 2015)

Jan 2015: 2c/7 orthogonal spaceship synthesis [Martin Grant, Tanner Jacobi]

Jan 2015: Gun for a half-baked knightship [Chris Cain] (a gun was likely constructed by [Michael Simkin] in Dec 2014, but it was too big to run in Golly)

Dec 2014: (versatile) (23,5)c/79 puffer [Brett Berger, Ivan Fomichev with Nicolay Beluchenko]

Dec 2014: c/3 orthogonal spaceship gun [Martin Grant, Michael Simkin with David Bell]

Sep 2014: (versatile) 31c/240 orthogonal puffer [Dave Greene, Ivan Fomichev, Adam P. Goucher, Chris Cain, with Kiho Park]

May 2014: versatile 2c/7 orthogonal puffer [Ivan Fomichev]

Dec 2013: 2c/7 orthogonal puffer [Ivan Fomichev]

Mar 2013: c/5 orthogonal wickstretcher [Matthias Merzenich]

Feb 2013: c/7 orthogonal spaceship gun [Shannon Omick, Matthias Merzenich, Adam P. Goucher with Josh Ball]

Jan 2011: c/5 diagonal wickstretcher [Matthias Merzenich]

Sep 2010: (versatile) c/5 diagonal puffer [Matthias Merzenich]

Jul 2010: Gun for Gemini spaceship [Dave Greene]

Oct 2005: versatile c/4 diagonal puffer [David Bell with Jason Summers, Nicolay Beluchenko]

Dec 2004: (versatile) 17c/45 orthogonal puffer [Gabriel Nivasch, Jason Summers with David Bell]

Mar 2004: c/4 diag puffer [Hartmut Holzwart]

Mar 2003: 2c/5 orthogonal spaceship gun [Noam Elkies, Dave Greene]

Oct 2002: c/2 wickstretcher [Dean Hickerson, Jason Summers]

Oct 2000: versatile c/4 puffer [David Bell, Jason Summers]

Jun 2000: versatile 2c/5 puffer [David Bell, Jason Summers with Paul Tooke]

Jul 1999: c/12 gun [Stephen Silver, Jason Summers]

Mar 1999: c/12 wickstretcher [Jason Summers with Dean Hickerson, David Buckingham]

Feb 1999: 2c/5 puffer [Jason Summers]

Jan 1999: c/4 puffer [Jason Summers]

Jun 1998: versatile c/12 puffers [Stephen Silver, Dean Hickerson]

Sep 1997: versatile c/5 puffers [David Bell]

May 1997: c/5 puffer [Tim Coe, David Bell]

Jun 1996: versatile c/3 puffers [David Bell]

Apr 1996: c/3 puffer [David Bell]

## Spaceship periods

This table lists the known spaceship periods up to 36 for each velocity. Periods not possible at any of the known velocities are omitted to save space.

Yellow means that only "trivial" examples exist, with no single section that repeats at the full period.

Velocity | Period | ||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|

2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 12 | 14 | 15 | 16 | 18 | 20 | 21 | 22 | 24 | 25 | 26 | 27 | 28 | 30 | 32 | 33 | 34 | 35 | 36 | other | |

c/2 orth | 2 | 4 | 6 | 8 | 10 | 12 | 14 | 16 | 18 | 20 | 22 | 24 | 26 | 28 | 30 | 32 | 34 | 36 | ... | ||||||||||

c/3 orth | 3 | 6 | 9 | 12 | 15 | 18 | 21 | 24 | 27 | 30 | 33 | 36 | ... | ||||||||||||||||

c/4 orth | 4 | 8 | 12 | 16 | 20 | 24 | 28 | 32 | 36 | ... | |||||||||||||||||||

c/4 diag | 4 | 8 | 12 | 16 | 20 | 24 | 28 | 32 | 36 | ~4508, ... | |||||||||||||||||||

2c/5 orth | 5 | 10 | 15 | 20 | 25 | 30 | 35 | ... | |||||||||||||||||||||

c/5 orth | 5 | 10 | 15 | 20 | 25 | 30 | 35 | 60, ... | |||||||||||||||||||||

c/5 diag | 5 | 10 | 15 | 20 | 25 | 30 | 35 | 85, ... | |||||||||||||||||||||

c/6 orth | 6 | 12 | 18 | 24 | 30 | 36 | None | ||||||||||||||||||||||

c/6 diag | 6 | 12 | 18 | 24 | 30 | 36 | None | ||||||||||||||||||||||

c/7 orth | 7 | 14 | 21 | 28 | 35 | 1204, ... | |||||||||||||||||||||||

2c/7 orth | 7 | 14 | 21 | 28 | 35 | ~1162, ... | |||||||||||||||||||||||

3c/7 orth | 7 | 14 | 21 | 28 | 35 | None | |||||||||||||||||||||||

c/7 diag | 7 | 14 | 21 | 28 | 35 | None | |||||||||||||||||||||||

c/10 orth | 10 | 20 | 30 | 320, ... | |||||||||||||||||||||||||

c/12 diag | 12 | 24 | 36 | 96, 192, ... | |||||||||||||||||||||||||

17c/45 orth | 270, ... | ||||||||||||||||||||||||||||

(23,5)c/79 | 158, ... | ||||||||||||||||||||||||||||

31c/240 orth | 240, ... |

**Most recent discoveries, excluding new velocities:**

Jun 2016: 3c/7 orth p28 [Tim Coe, Stephen Silver]

Sep 2015: nontrivial c/3 orth p30 [Matthias Merzenich, Josh Ball]

Oct 2010: c/4 orth p24 [Matthias Merzenich]

Sep 2005: c/4 diag p12 [Hartmut Holzwart]

Nov 2004: c/5 orth p10 [Paul Tooke]

Nov 2003: c/4 orth p32 [Paul Tooke with Jason Summers]

Feb 2003: c/2 orth p18 [Paul Tooke]

Dec 2002: nontrivial c/3 orth p18 [David Bell, Jason Summers]

Oct 2002: c/3 orth p27 [Paul Tooke]

May 2002: 2c/5 orth p35 [Paul Tooke]

8 Feb 2002: 2c/5 orth p15 and p25 [Paul Tooke]

4 Feb 2002: 2c/5 orth p20 and p30 [Paul Tooke]

14 Jan 2002: c/3 orth p21 [Paul Tooke]

8 Jan 2002: c/2 orth p30 [Paul Tooke]

Dec 2001: c/2 orth p10 and p14 [Paul Tooke]

May 2001: c/2 orth p22 [David Bell, Paul Tooke with Jason Summers]

Apr 2001: c/2 orth p26 [David Bell, Paul Tooke]

Dec 2000: c/4 diag p8 [Jason Summers]

Nov 2000: c/3 orth p12 [David Bell, Jason Summers]

Oct 2000: c/4 orth p8 and p12 [Jason Summers], and resulting trivial p24

Sep 2000: c/4 orth p20 [David Bell with Jason Summers]

May 2000: 2c/5 orth p10 [David Bell, Paul Tooke]

Feb 1999: c/3 orth p6 [Stephen Silver], and resulting trivial p18 and p30

May 1998: c/5 orth p30 [David Bell with Noam Elkies]

Mar 1998: c/3 orth p36 [David Bell]

Dec 1997: c/5 orth p15 [Noam Elkies with Tim Coe]

Apr 1996: c/3 orth p24 [David Bell]

?May 1994: c/2 orth p28 [Hartmut Holzwart with Alan Hensel]

Dec 1993: c/3 orth p15 [David Bell]

Jul 1993: c/2 orth p6 [David Bell]

May 1992: c/3 orth p9 [David Bell]