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A099733
a(n) is the number of active cells after a solid n X n square has reached a static state or constant population, closed and infinite loop in Conway's Game of Life.
3
0, 4, 12, 0, 24, 8, 12, 0, 52, 8, 12, 0, 4, 8, 0, 56, 72, 40, 60, 0, 52, 24, 92, 48, 28, 96, 312, 40
OFFSET
1,2
COMMENTS
Starting population for n is n^2.
a(n)=0 for n={1,4,8,12,15,20,..?..}, meaning that after a particular, finite number of generations, the grid is forever empty.
a(n) reaches a nonempty, single static state after a particular, finite number of generations for n={2,5,6,10,13,14,16,18,22,24,26,27,28,..?..}.
a(n) enters a constant population, infinite, two-state and closed loop after a particular, finite number of generations for n={3,7,9,11,17,19,21,23,25,..?..}.
For even generations > 153, a(29)=128. For odd generations > 153, a(29)=120. n=29 is the first value of a(n) for which the system enters a two-state loop with variable population after a particular, finite number of generations.
LINKS
Eric Weisstein's World of Mathematics, Game of Life
EXAMPLE
a(5)=24 because a 5 X 5 solid square placed on an otherwise empty grid at generation 0 in Conway's Game of Life will enter a static state at generation 11 with 24 cells forever alive/active/on.
CROSSREFS
Sequence in context: A354777 A218858 A014458 * A350259 A330989 A073902
KEYWORD
nonn,more
AUTHOR
Joseph Biberstine (jrbibers(AT)indiana.edu), Nov 08 2004
STATUS
approved