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A269522
Number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 622", based on the 5-celled von Neumann neighborhood.
4
1, 5, 9, 21, 25, 37, 57, 69, 89, 101, 121, 133, 169, 205, 257, 309, 361, 333, 377, 381, 385, 461, 465, 509, 601, 653, 697, 781, 889, 845, 1097, 1077, 1353, 1205, 1305, 1349, 1345, 1357, 1321, 1437, 1553, 1589, 1601, 1709, 1729, 1813, 1937, 2069, 2361, 2181
OFFSET
0,2
COMMENTS
Initialized with a single black (ON) cell at stage zero.
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 170.
MATHEMATICA
rule=622; stages=300; ca=CellularAutomaton[ {rule, {2, {{0, 2, 0}, {2, 1, 2}, {0, 2, 0}}}, {1, 1}}, {{{1}}, 0}, stages]; (* Start with single black cell *) Map[Function[Apply[Plus, Flatten[#1]]], ca] (* Count ON cells at each stage *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Robert Price, Feb 28 2016
STATUS
approved