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A306707
Expansion of Sum_{k>=0} x^(k^2) / Product_{j=1..k} (1 + j*x^j).
1
1, 1, -1, 1, 0, 0, -2, 2, 2, -1, -7, 5, 8, -4, -22, 23, 30, -32, -101, 102, 160, -81, -434, 288, 515, -249, -1393, 1542, 1756, -1950, -6694, 7040, 10192, -4724, -29594, 18851, 30282, -9298, -89627, 106068, 97255, -127909, -453650, 498939, 641627, -207845, -2026461
OFFSET
0,7
MATHEMATICA
nmax = 46; CoefficientList[Series[Sum[x^(k^2)/Product[(1 + j x^j), {j, 1, k}], {k, 0, nmax}], {x, 0, nmax}], x]
CROSSREFS
Sequence in context: A086612 A128207 A340740 * A180958 A295854 A230630
KEYWORD
sign
AUTHOR
Ilya Gutkovskiy, Mar 05 2019
STATUS
approved