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A249668 Population of the n-th generation of the pattern 101//010 in the Life Without Death cellular automaton. 1
3, 4, 7, 10, 15, 20, 25, 30, 38, 47, 55, 63, 69, 79, 91, 96, 105, 112, 124, 134, 139, 144, 152, 157, 163, 168, 176, 183, 187, 195, 205, 217, 223, 229, 239, 247, 259, 273, 285, 289, 295, 303, 311, 323, 334, 339, 343, 351, 363, 375, 383, 389, 397, 405, 413, 423 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Each generation, a cell turns on if it has exactly three neighbors that are on. Cells never turn off.

This pattern grows indefinitely. No other connected 3-celled pattern does so.

LINKS

Eric M. Schmidt, Table of n, a(n) for n = 0..2500

LifeWiki, Life without death

Index entries for linear recurrences with constant coefficients, signature (1,0,0,0,0,1,-1). (Initial terms do not obey recurrence; see formula section.)

FORMULA

For n >= 2108, a(n+6) = a(n) + 260. - Eric M. Schmidt, Nov 04 2014

For n >= 2115, a(n) = a(n-1) + a(n-6) - a(n-7). - Eric M. Schmidt, Nov 05 2014

EXAMPLE

Generation 0:

101

010

Generation 1:

111

010

Generation 2:

010

111

111

Generation 3:

111

111

111

010

Generation 4:

00100

01110

11111

01110

01110

CROSSREFS

Cf. A097981, A151725, A151731.

Sequence in context: A236475 A287458 A050572 * A105343 A237834 A147789

Adjacent sequences:  A249665 A249666 A249667 * A249669 A249670 A249671

KEYWORD

nonn

AUTHOR

Eric M. Schmidt, Nov 03 2014

STATUS

approved

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Last modified December 13 22:55 EST 2019. Contains 329974 sequences. (Running on oeis4.)