A004830 -id:A004830 - cp's OEIS frontend

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

N. J. A. Sloane, Nov 25 2010

nonn

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

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.

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.

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

A214922 Numbers of the form x^2 + y^2 + z^3 + w^3 (x, y, z, w >= 0).

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54

Offset: 1

Philippe Deléham, Jul 20 2012

nonn

Conjecture: 23 is the only number not in this sequence.
Not the same as A004830: 239 is a term of this sequence but not of A004830. - R. J. Mathar and Joerg Arndt, Jul 28 2012
There are no other missing numbers from 24 to 10^8. - Giovanni Resta, Oct 12 2019

			22 = 2^2 + 4^2 + 1^3 + 1^3, 22 is in this sequence.

Cf. A001481, A004999, A022549, A022550, A022551, A022552.

cp's OEIS Frontend

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

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