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A281591
First differences of A281590.
3
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
1,1
LINKS
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]
CROSSREFS
Sequence in context: A354213 A343460 A224831 * A267884 A370088 A077859
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, Apr 14 2017
STATUS
approved