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A024275
E.g.f: log(1+sinh(x)*sin(x))/2 (even powers only).
0
0, 1, -6, 116, -4816, 342736, -37272576, 5748462656, -1193465153536, 320935235205376, -108513125117853696, 45057835625375568896, -22540295648947188269056, 13370560809273727964041216
OFFSET
0,3
EXAMPLE
log(1+sinh(x)*sin(x))/2 = 0 + 1/2*x^2 - 1/4*x^4 + 29/180*x^6 - 43/360*x^8 + 21421/226800*x^10 +- ... .
MATHEMATICA
With[{nn=30}, Take[CoefficientList[Series[Log[1+Sinh[x]*Sin[x]]/2, {x, 0, nn}], x] Range[0, nn]!, {1, -1, 2}]] (* Harvey P. Dale, Mar 01 2019 *)
CROSSREFS
Cf. A009359.
Sequence in context: A229582 A113015 A362765 * A287652 A259064 A300733
KEYWORD
sign
AUTHOR
EXTENSIONS
Extended with signs, Mar 1997
Prior Mathematica program replaced by Harvey P. Dale, Mar 01 2019
STATUS
approved