A072457 Shadow transform of tetrahedral numbers A000292.

0, 1, 1, 1, 2, 3, 1, 3, 2, 1, 4, 3, 3, 3, 4, 3, 2, 3, 1, 3, 7, 2, 4, 3, 3, 3, 4, 1, 7, 3, 3, 3, 2, 2, 4, 9, 2, 3, 4, 3, 7, 3, 6, 3, 7, 2, 4, 3, 2, 3, 4, 4, 7, 3, 1, 9, 7, 4, 4, 3, 6, 3, 4, 4, 2, 9, 4, 3, 7, 3, 13, 3, 2, 3, 4, 2, 7, 9, 4, 3, 7, 1, 4, 3, 8, 9, 4, 2, 7, 3, 4, 9, 7, 3, 4, 9, 3, 3, 4, 3, 7, 3, 3, 3, 7

Offset

0,5

Links

Alois P. Heinz, Table of n, a(n) for n = 0..10000

Lorenz Halbeisen and Norbert Hungerbuehler, Number theoretic aspects of a combinatorial function, Notes on Number Theory and Discrete Mathematics 5(4) (1999), 138-150. (ps, pdf); see Definition 7 for the shadow transform.

OEIS Wiki, Shadow transform.

N. J. A. Sloane, Transforms.

Maple

a:= n-> add(`if`(modp(j*(j+1)*(j+2)/6, n)=0, 1, 0), j=0..n-1):
seq(a(n), n=0..120);  # Alois P. Heinz, Sep 16 2019

Crossrefs

Cf. A000292.

Sequence in context: A007413 A277750 A325520 * A364554 A301630 A063047

Adjacent sequences: A072454 A072455 A072456 * A072458 A072459 A072460

Keyword

nonn

Author

N. J. A. Sloane, Aug 02 2002

Status

approved