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A266901
Total number of OFF (white) cells after n iterations of the "Rule 75" elementary cellular automaton starting with a single ON (black) cell.
1
0, 2, 4, 7, 11, 17, 25, 31, 41, 50, 63, 72, 87, 97, 116, 129, 149, 165, 188, 203, 227, 243, 273, 292, 322, 340, 379, 395, 430, 454, 491, 518, 557, 584, 629, 650, 696, 729, 774, 805, 856, 882, 938, 969, 1022, 1055, 1110, 1147, 1210, 1239, 1308, 1343, 1403
OFFSET
0,2
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
MATHEMATICA
rule=75; 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. A266892.
Sequence in context: A122051 A073471 A308825 * A117649 A028291 A067997
KEYWORD
nonn,easy
AUTHOR
Robert Price, Jan 05 2016
STATUS
approved