A281591 First differences of A281590.

3, 5, 6, 5, 7, 6, 8, 7, 8, 8, 8, 8, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 11, 11, 10, 11, 12, 11, 11, 12, 11, 12, 12, 12, 12, 13, 12, 13, 12, 13, 13, 13, 13, 13, 13, 13, 14, 13, 14, 13, 14, 14, 14, 14, 14, 14, 15, 14, 15, 14, 15, 14, 15, 15, 15, 15, 15, 15, 16

Offset: 1

Author

Vaclav Kotesovec, Apr 14 2017

Keywords

• nonn

Links

• Vaclav Kotesovec, Table of n, a(n) for n = 1..2611

Crossrefs

Cf. A284896, A281590.

Programs

Mathematica

nmax = 1000; A284896 = Rest[CoefficientList[Series[Product[1/(1 + x^k)^(k^2), {k, 1, nmax}], {x, 0, nmax}], x]]; csign = {1}; Do[If[(A284896[[n]] < 0 && A284896[[n+1]] >= 0) || (A284896[[n]] >= 0 && A284896[[n+1]] < 0), csign = Flatten[{csign, n + 1}]], {n, 1, Length[A284896] - 1}]; Differences[csign]