A118816 A fractal sequence based upon powers of 3.

1, 0, 1, 1, 1, 0, 2, 2, 1, 3, 3, 1, 4, 4, 1, 5, 5, 0, 6, 6, 2, 7, 7, 2, 8, 8, 1, 9, 9, 3, 10, 10, 3, 11, 11, 1, 12, 12, 4, 13, 13, 4, 14, 14, 1, 15, 15, 5, 16, 16, 5, 17, 17, 0, 18, 18, 6, 19, 19, 6, 20, 20, 2, 21, 21, 7, 22, 22, 7, 23, 23, 2, 24, 24, 8, 25, 25, 8, 26, 26, 1, 27, 27, 9, 28, 28

Offset: 1

Author

Robert G. Wilson v, May 23 2006

Keywords

• nonn

Comments

Zeros occur at A008776, or 2*3^(k-1), k > 0.

Links

• Index entries for sequences related to "fractals"

Crossrefs

Cf. A003602, A101279.

Programs

Mathematica

a[1] = 1; a[n_] := Switch[ Mod[n, 3], 0, a[n/3], 1, (n - 1)/3, 2, (n - 2)/3]; Array[a, 90]

Formula

a((3n-2)/3) = A028310(n), a((3n-1)/3) =A001477 & a(3n)=a(n), thus this sequence is a fractal.