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A089520
In Conway's Game of Life, the number of steps it takes for an n X n square, in which all the cells are in the "on" state, to die out or start to cycle, or -1 if there is no cycle.
3
1, 0, 5, 4, 11, 5, 5, 6, 16, 17, 32, 9, 18, 9, 22, 11, 33, 17, 20, 12, 26, 13, 48, 15, 46, 26, 295, 45, 154, 38, 62, 309, 38, 87, 78, 53, 96, 150, 641, 69, 82, 265, 216, 70, 70, 70, 120, 401, 107, 78, 70, 351, 318, 109, 297, 95, 122, -1, -1, 85, 232, 294, 127
OFFSET
1,3
COMMENTS
The -1 terms for n = 58, 59, 80, 92, 95, 96, 98, 99, 100 correspond to starting n x n squares that produce 8 gliders (16 for n = 99) that go off to infinity, hence never reaching a cycle. - Michael S. Branicky, Jul 06 2022
LINKS
Michael S. Branicky, Table of n, a(n) for n = 1..100
Michael S. Branicky, Python program and utilities.
D. Griffeath, Life32 by Johan Bontes.
Nathaniel Johnston, ConwayLife.com.
S. Silver, Life Lexicon.
EXAMPLE
a(1) = 1 since a single cell is switched off on step 1.
a(2) = 0 since a block is cyclic to start with: 0th = 1st generation.
a(3) = 5 since a cycle starts there: 5th = 7th generation.
CROSSREFS
Sequence in context: A309545 A285105 A360682 * A163524 A330614 A051552
KEYWORD
sign
AUTHOR
Anne M. Donovan (anned3005(AT)aol.com), Nov 05 2003
EXTENSIONS
More terms from John W. Layman, Nov 07 2003
39 more terms from Rick L. Shepherd, Jun 04 2004
Name edited, a(58) and a(59) changed, and a(61) and beyond from Michael S. Branicky, Jul 06 2022
STATUS
approved