A303485 a(n) = [x^(n^3)] (1/(1 - x))*(Sum_{k>=1} x^(k^3))^n.

1, 1, 1, 8, 66, 512, 5269, 57459, 711742, 9610222, 139735699, 2183555015, 36543300668, 649320343729, 12174674648730, 240360451018461, 4975239937954534, 107600744797471150, 2426579187889852885, 56901290353169050995, 1384258146777832889697

Offset: 0

Author

Ilya Gutkovskiy, Apr 24 2018

Keywords

• nonn

Comments

Number of positive solutions to (x_1)^3 + (x_2)^3 + ... + (x_n)^3 <= n^3.

Links

• Index entries for sequences related to sums of cubes

Crossrefs

Cf. A000578, A010057, A051344, A280618, A298672, A302995, A303169.

Programs

Mathematica

Join[{1}, Table[SeriesCoefficient[1/(1 - x) Sum[x^k^3, {k, 1, n}]^n, {x, 0, n^3}], {n, 20}]]