A166493 A Per Bak sand pile collapse sequence using Hofstadter Q:A005185, of the A153112 form.

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

Author

Roger L. Bagula, Oct 15 2009

Keywords

• nonn
• uned

Crossrefs

Cf. A153112, A005185.

Programs

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}]