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A280865
Expansion of 1/(1 - Sum_{k>=0} x^((2*k+1)^3)).
1
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 30, 33, 37, 42, 48, 55, 63, 72, 82, 93, 105, 118, 132, 147, 163, 180, 198, 217, 237, 258, 280, 303, 327, 352, 378, 405, 433, 463, 496
OFFSET
0,28
COMMENTS
Number of compositions (ordered partitions) of n into odd cubes (A016755).
FORMULA
G.f.: 1/(1 - Sum_{k>=0} x^((2*k+1)^3)).
EXAMPLE
a(28) = 3 because we have [27, 1], [1, 27] and [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1].
MATHEMATICA
nmax = 82; CoefficientList[Series[1/(1 - Sum[x^(2 k + 1)^3, {k, 0, nmax}]), {x, 0, nmax}], x]
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Jan 09 2017
STATUS
approved