This week's featured article
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| A polyomino (or simply omino) is a finite collection of orthogonally connected cells. Conway's early investigations of Life and other cellular automata involved tracking the histories of small polyominoes, this being a reasonable way to ascertain the typical behaviour of different cellular automata when the patterns had to be evolved by hand rather than by computer. Polyominoes have no special significance in Life, but their extensive study during the early years lead to a number of important discoveries and has influenced the terminology of Life.
It is possible for a polyomino to be an oscillator. In fact, there are infinitely many examples of such polyominoes, including the cross and its larger analogues. The only other known examples are the block (which has period 1), the blinker, the toad, the star (and its hybrid with cross that gives another extensible family of period-3 oscillators) and (in two different phases) the pentadecathlon.
A polyomino can also be a spaceship, though the only known examples are the lightweight spaceship, the middleweight spaceship, and the heavyweight spaceship.
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In the news
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Pattern collection
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| The LifeWiki contains one of the most comprehensive catalogues of patterns available on the internet. Within it you will find:
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Did you know...
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- ... that two completely different types of oblique spaceships, the waterbear and the half-baked knightship, were constructed in 2014?
- ... that no Caterpillar-type spaceships were completed for almost ten years after the original Caterpillar was constructed in 2004, but that two different designs, the waterbear and the centipede, were finished in 2014?
- ... that the first spiral-growth pattern in Conway's Life was constructed in 2014?
- ... that among known glider recipes for irreducible objects, the Gemini spaceship has the largest known minimal recipe not counting encoded RCT recipes, currently 173,449 gliders — the runner-up being the self-synthesizing oblique loopship which is its own 144,221-glider synthesis?
- ... that it was shown in 2014 that any salvo of gliders, no matter how tightly packed, can be constructed by crashing together gliders whose initial positions are farther apart than any chosen finite distance?
- ... that no spaceships with velocities other than c/4 diagonal (glider), c/2 orthogonal (*WSS variants), and c/12 diagonal (Corderships) had known glider syntheses until 2003, when a 2c/5 spaceship gun was constructed?
- ... that after ten years with no new small spaceship syntheses, a glider construction was found for the c/7 loafer in 2013 less than three hours after its discovery?
- ... that a spaceship made of spaceships was only a theoretical concept in Conway's Life (except for 0E0P metacell patterns that were much too large to run) until an explicit universal constructor based example was constructed in 2021?
- ... that glider constructions for the B29, X66, half-X66 with HWSS, Pushalong 1, 25P3H1V0.1, 30P5H2V0, 30P4H2V0, a pufferfish spaceship, and the weekender were discovered in 2015 — more than twice as many new spaceship recipes as had been completed in the entire previous decade?
- ... that in 2014 and 2015 alone, more new spaceship syntheses have been completed than were found in all the years between 1970 and 2013?
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