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A267369
Total number of OFF (white) cells after n iterations of the "Rule 126" elementary cellular automaton starting with a single ON (black) cell.
1
0, 0, 1, 1, 6, 9, 14, 14, 27, 38, 51, 58, 75, 86, 99, 99, 128, 155, 184, 207, 240, 267, 296, 311, 352, 387, 424, 447, 488, 515, 544, 544, 605, 664, 725, 780, 845, 904, 965, 1012, 1085, 1152, 1221, 1276, 1349, 1408, 1469, 1500, 1589, 1672, 1757, 1828, 1917
OFFSET
0,5
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
MATHEMATICA
rule=126; 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. A071035.
Sequence in context: A176212 A232553 A155705 * A177891 A370125 A367947
KEYWORD
nonn,easy
AUTHOR
Robert Price, Jan 13 2016
STATUS
approved