A269339 Expansion of Product_{k>=1} (1 - k*x^k) / (1 + x^k).

1, -2, -1, 0, 2, 6, -3, 12, -13, -2, -15, 2, -65, 44, 37, -90, 134, 26, 334, -270, 66, 18, 774, -1280, -15, -2266, 2627, -352, -3575, -516, -484, 5660, -3629, 21408, -20639, -1228, 15595, 31796, -22214, 55390, -104447, 58958, -160254, 180704, 17402, -103200

Offset: 0

Author

Vaclav Kotesovec, Feb 24 2016

Keywords

• sign

Links

• Vaclav Kotesovec, Table of n, a(n) for n = 0..5000

Crossrefs

Cf. A022661, A081362, A267004, A267005, A268500.

Programs

Mathematica

nmax=50; CoefficientList[Series[Product[(1-k*x^k)/(1+x^k), {k, 1, nmax}], {x, 0, nmax}], x]