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A166493
A Per Bak sand pile collapse sequence using Hofstadter Q:A005185, of the A153112 form.
0
1, 1, 1, 2, 3, 3, 4, 5, 5, 6, 6, 6, 8, 8, 8, 10, 9, 10, 1, 7, 15, 12, 11, 14, 14, 12, 16, 16, 16, 16, 16, 20, 17, 17, 20, 11, 21, 25, 18, 20, 26, 22, 24, 19, 27, 17, 23, 30, 13, 28, 36, 24, 25, 32, 27, 30, 32, 28, 32, 36, 30, 32, 3, 50, 40, 22, 43, 31, 37, 35, 28, 40, 44, 33, 38, 49
OFFSET
0,4
MATHEMATICA
f[0] = 1; f[1] = 1; f[2] = 1;
f[n_] := f[n] = If[Mod[Floor[Sum[f[i], {i, 0, n - 1}]/2], 2^(4 + Mod[n, 3])] == 0, 1 + Mod[n, 3], f[n - f[n - 1]] + f[n - f[n - 2]]];
a = Table[f[n], {n, 0, 200}]
CROSSREFS
Sequence in context: A296020 A266350 A123579 * A005185 A119466 A100922
KEYWORD
nonn,uned
AUTHOR
Roger L. Bagula, Oct 15 2009
STATUS
approved