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A266813
Total number of OFF (white) cells after n iterations of the "Rule 62" elementary cellular automaton starting with a single ON (black) cell.
3
0, 0, 2, 3, 7, 10, 14, 19, 26, 31, 39, 47, 56, 65, 76, 86, 99, 111, 124, 138, 154, 168, 185, 202, 220, 238, 258, 277, 299, 320, 342, 365, 390, 413, 439, 465, 492, 519, 548, 576, 607, 637, 668, 700, 734, 766, 801, 836, 872, 908, 946, 983, 1023, 1062, 1102
OFFSET
0,3
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
FORMULA
From Colin Barker, Jan 04 2016 and Apr 17 2019: (Start)
a(n) = a(n-1)+a(n-3)-a(n-5)-a(n-7)+a(n-8) for n>7.
G.f.: x^2*(2+x+4*x^2+x^3+x^4) / ((1-x)^3*(1+x)*(1+x^2)*(1+x+x^2)).
(End)
MATHEMATICA
rule=62; 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. A071031, A266811 (total OFF cells).
Partial sums of A071046.
Sequence in context: A002238 A002255 A272649 * A344232 A370639 A361859
KEYWORD
nonn,easy
AUTHOR
Robert Price, Jan 03 2016
STATUS
approved