A009351 Expansion of log(1+sinh(x))*cos(x).

0, 1, -1, 0, -4, 20, -121, 896, -7344, 68304, -711721, 8200192, -103603204, 1424807488, -21191898001, 339004274688, -5804468899584, 105924311382272, -2052443682726961, 42085719065821184, -910506730330968484

Offset

0,5

Links

Table of n, a(n) for n=0..20.

Formula

a(n) ~ (n-1)! * (-1)^(n+1) * cos(log(1+sqrt(2))) / (log(1+sqrt(2)))^n. - Vaclav Kotesovec, Jan 23 2015

Mathematica

Log[ 1+Sinh[ x ] ]*Cos[ x ]
CoefficientList[Series[Cos[x]*Log[1 + Sinh[x]], {x, 0, 20}], x] * Range[0, 20]! (* Vaclav Kotesovec, Jan 23 2015 *)

Crossrefs

Sequence in context: A304069 A020028 A020118 * A379202 A121553 A067116

Adjacent sequences: A009348 A009349 A009350 * A009352 A009353 A009354

Keyword

sign,easy

Author

R. H. Hardin

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Status

approved