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A306704
Expansion of Sum_{k>=0} x^(k*(k+1)/2) / Product_{j=1..k} (1 + j*x^j).
1
1, 1, -1, 2, -2, 0, 1, 3, -5, -6, 11, 11, -12, -35, 33, 35, -22, -102, 170, 47, -224, -491, 874, 695, -598, -2606, 2246, 1503, -664, -6420, 11590, 2526, -13762, -34647, 61785, 37119, -32372, -181052, 147105, 104896, 12824, -436333, 799007, -109587, -868230, -2316921, 4447531
OFFSET
0,4
MATHEMATICA
nmax = 46; CoefficientList[Series[Sum[x^(k (k + 1)/2)/Product[(1 + j x^j), {j, 1, k}], {k, 0, nmax}], {x, 0, nmax}], x]
CROSSREFS
Sequence in context: A130020 A292870 A378291 * A091063 A246935 A342120
KEYWORD
sign
AUTHOR
Ilya Gutkovskiy, Mar 05 2019
STATUS
approved