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A169709 Total number of ON cells at stage n of two-dimensional cellular automaton defined by "Rule 1006". 2
1, 5, 9, 21, 29, 41, 61, 89, 101, 113, 133, 161, 189, 233, 309, 377, 397, 409, 429, 457, 485, 529, 605, 673, 709, 753, 821, 905, 1005, 1169, 1413, 1569, 1605, 1617, 1637, 1665, 1693, 1737, 1813, 1881, 1917, 1961, 2029, 2113, 2213, 2377, 2621, 2777, 2829, 2873, 2941 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Square grid, 4 neighbors per cell, turn ON iff exactly 1, 3 or 4 neighbors are ON; once ON, cells stay ON.

REFERENCES

S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 928.

LINKS

Table of n, a(n) for n=0..50.

MATHEMATICA

Map[Function[Apply[Plus, Flatten[ #1]]], CellularAutomaton[{ 1006, {2, {{0, 2, 0}, {2, 1, 2}, {0, 2, 0}}}, {1, 1}}, {{{1}}, 0}, 100]]

CROSSREFS

Cf. A169710, A147562, A147582, A169648, A169649, A169707, A169708.

Sequence in context: A147407 A186297 A169649 * A211427 A146867 A068481

Adjacent sequences:  A169706 A169707 A169708 * A169710 A169711 A169712

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Apr 17 2010

STATUS

approved

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Last modified November 23 05:04 EST 2014. Contains 249839 sequences.