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A265284
Total number of ON (black) cells after n iterations of the "Rule 94" elementary cellular automaton starting with a single ON (black) cell.
3
1, 4, 8, 14, 20, 28, 36, 46, 56, 68, 80, 94, 108, 124, 140, 158, 176, 196, 216, 238, 260, 284, 308, 334, 360, 388, 416, 446, 476, 508, 540, 574, 608, 644, 680, 718, 756, 796, 836, 878, 920, 964, 1008, 1054, 1100, 1148, 1196, 1246, 1296, 1348, 1400, 1454
OFFSET
0,2
REFERENCES
S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.
FORMULA
Conjectures from Colin Barker, Dec 07 2015 and Apr 16 2019: (Start)
a(n) = (2*n^2+12*n-(-1)^n+1)/4 for n>0.
a(n) = (n^2+6*n)/2 for n>1 and even.
a(n) = (n^2+6*n+1)/2 for n odd.
a(n) = 2*a(n-1) - 2*a(n-3) + a(n-4) for n>4.
G.f.: (1+2*x-x^4) / ((1-x)^3*(1+x)).
(End)
MATHEMATICA
rule = 94; rows = 30; Table[Total[Take[Table[Total[Table[Take[CellularAutomaton[rule, {{1}, 0}, rows-1, {All, All}][[k]], {rows-k+1, rows+k-1}], {k, 1, rows}][[k]]], {k, 1, rows}], k]], {k, 1, rows}]
CROSSREFS
Cf. A118102.
Sequence in context: A232996 A317292 A276221 * A055507 A343880 A121896
KEYWORD
nonn,easy
AUTHOR
Robert Price, Dec 06 2015
STATUS
approved