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A267151
Total number of OFF (white) cells after n iterations of the "Rule 105" elementary cellular automaton starting with a single ON (black) cell.
1
0, 3, 5, 10, 16, 25, 33, 44, 58, 67, 79, 94, 114, 129, 147, 168, 198, 207, 235, 250, 282, 309, 339, 372, 416, 431, 469, 494, 540, 573, 613, 656, 718, 727, 787, 802, 866, 893, 955, 988, 1060, 1087, 1145, 1190, 1264, 1309, 1369, 1432, 1524, 1539, 1625, 1650
OFFSET
0,2
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
MATHEMATICA
rule=105; 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. A267145.
Sequence in context: A287563 A184800 A350237 * A209008 A032279 A070558
KEYWORD
nonn,easy
AUTHOR
Robert Price, Jan 11 2016
STATUS
approved