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A173681
Number of ways of writing n as a sum of 8 nonnegative cubes.
12
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
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
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
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Nov 25 2010
STATUS
approved