128:. Second, stabilizations of puffers that eliminate all of their output debris can be used to produce spaceships with arbitrarily large periods. And third, puffers can sometimes be tamed or combined to form spaceships with speeds that do not seem to be achievable in other ways; for instance, in Life, the
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periods; the first is the period of the puffer itself, while the second is the apparent period of the pattern of debris produced. This is often the same as the period of the puffer, but sometimes is a factor of the period. A puffer for which the apparent period deduced from the debris is smaller
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puffer, conversely, has a small amount of debris that appears much more organized. A dirty puffer can sometimes be turned into a clean puffer by adding spaceships of the same velocity as the puffer that affect what debris results.
31:, is a finite pattern that moves itself across the "universe", leaving debris behind. Thus a pattern consisting of only a puffer will grow arbitrarily large over time. While both puffers and spaceships have
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for three reasons: First, if they can be stabilized in such a way that they produce only gliders (that is, turned into rakes) they can be used as part of many more complex patterns such as
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puffer is one in which there is little apparent order in the debris (although the debris will still eventually be periodic). A
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is a puffer train discovered by
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is one in which the period of the debris matches that of the puffer.
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A puffer whose debris consists entirely of spaceships is called a
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The period of a puffer can be considered as the combination of
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Gosper's puffer also appears in the cover art for this book.
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167:Wheels, Life and Other Mathematical Amusements
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70:. While there is no precise distinction, a
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164:(1983). "The Game of Life, Part III".
62:Puffers are divided into two classes,
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51:than the period of the engine is a
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140:/12 spaceship that he called the
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182:Jason Summers' Life status page
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170:. W.H. Freeman. p. 247.
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43:do not leave debris behind.
531:Cellular automaton patterns
112:The first known puffer, in
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401:Von Neumann neighborhood
205:Cordership, E. Weisstein
90:In Conway's Game of Life
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114:Conway's Game of Life
209:Cordership, Lifepage
116:, was discovered by
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251:and related
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464:Bill Gosper
454:John Conway
322:Spacefiller
162:Gardner, M.
118:Bill Gosper
447:Key people
430:Video Life
337:Still life
312:Replicator
292:Oscillator
287:Methuselah
260:Structures
148:References
142:Cordership
41:spaceships
327:Spaceship
307:Reflector
525:Category
485:LifeWiki
478:Websites
384:Concepts
360:Highlife
317:Sawtooth
197:Archived
126:breeders
267:Breeder
33:periods
277:Glider
37:speeds
29:puffer
502:Bloom
417:Golly
375:Seeds
365:Lenia
332:Spark
76:clean
72:dirty
19:In a
509:Wake
302:Rake
84:rake
66:and
35:and
23:, a
282:Gun
48:two
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241:e
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