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A281669
Expansion of Sum_{i>=1} x^(i^3)/(1 + x^(i^3)) * Product_{j>=1} (1 + x^(j^3)).
0
1, 0, 0, 0, 0, 0, 0, 1, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 0, 0, 0, 0, 0, 0, 2, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 0, 0, 0, 0, 0, 0, 2, 3, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 3, 0, 0, 0, 0, 0, 0, 3, 4
OFFSET
1,9
COMMENTS
Total number of parts in all partitions of n into distinct cubes.
FORMULA
G.f.: Sum_{i>=1} x^(i^3)/(1 + x^(i^3)) * Product_{j>=1} (1 + x^(j^3)).
EXAMPLE
a(36) = 3 because we have [27, 8, 1].
MATHEMATICA
nmax = 100; Rest[CoefficientList[Series[Sum[x^i^3/(1 + x^i^3), {i, 1, nmax}] Product[1 + x^j^3, {j, 1, nmax}], {x, 0, nmax}], x]]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Jan 26 2017
STATUS
approved