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A267519
Total number of OFF (white) cells after n iterations of the "Rule 137" elementary cellular automaton starting with a single ON (black) cell.
1
0, 3, 6, 11, 14, 19, 25, 33, 38, 44, 52, 60, 68, 79, 90, 103, 112, 123, 134, 147, 161, 177, 191, 205, 218, 231, 248, 270, 290, 306, 323, 347, 366, 380, 399, 424, 442, 462, 487, 511, 530, 554, 585, 612, 638, 662, 684, 716, 747, 775, 799, 828, 862, 892, 923
OFFSET
0,2
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
MATHEMATICA
rule=137; rows=20; ca=CellularAutomaton[rule, {{1}, 0}, rows-1, {All, All}]; (* Start with single black cell *) catri=Table[Take[ca[[k]], {rows-k+1, rows+k-1}], {k, 1, rows}]; (* Truncated list of each row *) nbc=Table[Total[catri[[k]]], {k, 1, rows}]; (* Number of Black cells in stage n *) nwc=Table[Length[catri[[k]]]-nbc[[k]], {k, 1, rows}]; (* Number of White cells in stage n *) Table[Total[Take[nwc, k]], {k, 1, rows}] (* Number of White cells through stage n *)
CROSSREFS
Cf. A267463.
Sequence in context: A189380 A047398 A047924 * A200182 A342173 A282277
KEYWORD
nonn,easy
AUTHOR
Robert Price, Jan 16 2016
STATUS
approved