A173681 Number of ways of writing n as a sum of 8 nonnegative cubes.

1, 8, 28, 56, 70, 56, 28, 8, 9, 56, 168, 280, 280, 168, 56, 8, 28, 168, 420, 560, 420, 168, 28, 0, 56, 280, 560, 568, 336, 224, 280, 280, 238, 336, 428, 336, 406, 840, 1120, 840, 392, 224, 168, 224, 840, 1680, 1680, 840, 196, 56, 28, 280, 1120, 1680, 1148, 448, 428, 568, 420, 448, 868, 840, 448, 840, 1689, 1736, 1008, 616, 616, 336, 476, 1688, 2576

Offset

0,2

Comments

Order matters. This is the coefficient of q^n in the expansion of {Sum_{m>=0} q^(m^3)}^8.

Links

Seiichi Manyama, Table of n, a(n) for n = 0..10000

L. E. Dickson, All integers except 23 and 239 are sums of eight cubes, Bull. Amer. Math. Soc. 45 (1939), 588-591.

Prog

(PARI) lista(n)=my(q='q); Vec(sum(m=0, (n+.5)^(1/3), q^(m^3), O(q^(n+1)))^8); \\ Michel Marcus, Apr 12 2016

Crossrefs

Cf. A004830, A173677.

Sums of k cubes, number of ways of writing n as, for k=1..9: A010057, A173677, A051343, A173678, A173679, A173680, A173676, A173681, A173682.

Sequence in context: A001486 A230211 A229393 * A045850 A264354 A033580

Adjacent sequences: A173678 A173679 A173680 * A173682 A173683 A173684

Keyword

nonn

Author

N. J. A. Sloane, Nov 25 2010

Status

approved