A069137 Numbers which are sums of neither 1, 2, 3, 4, 5 or 6 nonnegative cubes.

7, 14, 15, 21, 22, 23, 42, 47, 49, 50, 61, 77, 85, 87, 103, 106, 111, 112, 113, 114, 122, 140, 148, 159, 166, 167, 174, 175, 178, 185, 186, 204, 211, 212, 223, 229, 230, 231, 237, 238, 239, 276, 292, 295, 300, 302, 303, 311, 327, 329, 337, 340, 356, 363, 364

Offset

1,1

Comments

Sequence is conjectured to be finite.

References

Bohman, Jan and Froberg, Carl-Erik; Numerical investigation of Waring's problem for cubes, Nordisk Tidskr. Informationsbehandling (BIT) 21 (1981), 118-122.

F. Romani, Computations concerning Waring's problem, Calcolo, 19 (1982), 415-431.

Links

T. D. Noe, Table of n, a(n) for n=1..138

Jean-Marc Deshouillers, Francois Hennecart and Bernard Landreau; appendix by I. Gusti Putu Purnaba, 7373170279850, Math. Comp. 69 (2000), 421-439.

Index entries for sequences related to sums of cubes

Formula

Natural numbers remaining if union of A003325, A003072, A003327, A003328, A003329 and A000578 sets were deleted. Remark: this sequence itself does not include cubes, in contrast to A085334.

Example

Numbers which need at least seven terms to represent them as a sum of positive cubes: 14=8+1+1+1+1+1+1.

Crossrefs

Cf. A057907, A003329, A003325, A003072, A003327, A003328, A000578, A085334.

Sequence in context: A296705 A297138 A085335 * A141164 A004781 A004759

Adjacent sequences: A069134 A069135 A069136 * A069138 A069139 A069140

Keyword

nonn

Author

N. J. A. Sloane, Apr 08 2002; edited Sep 15 2006

Status

approved