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.

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

Author

Anne M. Donovan (anned3005(AT)aol.com), Nov 05 2003

Keywords

• sign

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

Examples

			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.
		

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.

Crossrefs

Cf. A019473, A086993.

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