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A246332
a(n) = if n is even, number of ON cells at stage n of two-dimensional 5-neighbor outer totalistic cellular automaton defined by "Rule 461" or if n is odd, number of OFF cells.
1
1, 1, 5, 5, 17, 9, 21, 21, 25, 33, 45, 49, 81, 69, 105, 81, 101, 101, 165, 141, 197, 185, 217, 209, 265, 245, 337, 269, 405, 325, 477, 389, 521, 461, 625, 469, 621, 485, 769, 585, 849, 737, 825, 705, 973, 713, 985, 841, 1089, 925, 1257, 969, 1229, 1093, 1265
OFFSET
0,3
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; pp. 173-175.
MATHEMATICA
Map[Function[Apply[Plus, Flatten[ #1]]], CellularAutomaton[{ 461, {2, {{0, 2, 0}, {2, 1, 2}, {0, 2, 0}}}, {1, 1}}, {{{1}}, 0}, 130]] (* then subtract the odd-indexed terms from 131^2 *)
ArrayPlot /@ CellularAutomaton[{461, {2, {{0, 2, 0}, {2, 1, 2}, {0, 2, 0}}}, {1, 1}}, {{{1}}, 0}, 23]
CROSSREFS
A246329 is a bisection.
Sequence in context: A273703 A253065 A294612 * A300784 A273326 A273421
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Aug 30 2014
STATUS
approved