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A267593
Total number of OFF (white) cells after n iterations of the "Rule 169" elementary cellular automaton starting with a single ON (black) cell.
1
0, 3, 6, 10, 13, 17, 21, 27, 30, 34, 38, 43, 47, 52, 57, 64, 67, 71, 75, 80, 84, 89, 94, 101, 105, 111, 117, 125, 131, 139, 147, 159, 162, 166, 170, 175, 179, 184, 189, 196, 200, 205, 210, 216, 221, 227, 233, 241, 245, 250, 255, 261, 266, 272, 278, 286, 291
OFFSET
0,2
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
MATHEMATICA
rule=169; 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. A264442.
Sequence in context: A288205 A049880 A276219 * A248221 A189368 A128039
KEYWORD
nonn,easy
AUTHOR
Robert Price, Jan 18 2016
STATUS
approved