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A266627
Total number of ON (black) cells after n iterations of the "Rule 45" elementary cellular automaton starting with a single ON (black) cell.
1
1, 2, 6, 8, 13, 20, 28, 36, 43, 56, 65, 77, 88, 106, 121, 139, 153, 176, 192, 214, 229, 259, 282, 305, 325, 361, 379, 409, 441, 471, 501, 535, 563, 600, 633, 677, 704, 756, 781, 834, 866, 913, 951, 1005, 1033, 1095, 1131, 1188, 1226, 1287, 1330, 1389, 1428
OFFSET
0,2
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
MATHEMATICA
rule=45; 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 *) Table[Total[Take[nbc, k]], {k, 1, rows}] (* Number of Black cells through stage n *)
CROSSREFS
Cf. A266619.
Sequence in context: A356217 A294862 A087327 * A289753 A002511 A074383
KEYWORD
nonn,easy
AUTHOR
Robert Price, Jan 01 2016
STATUS
approved