A009328 Expansion of log(1+sin(sinh(x))).

0, 1, -1, 2, -6, 16, -72, 328, -1904, 12160, -89344, 721280, -6445824, 62638720, -660602880, 7495723264, -91175548928, 1182630301696, -16301080281088, 237887012458496, -3664597991424000, 59422015832915968

Offset

0,4

Links

Table of n, a(n) for n=0..21.

Formula

a(n) ~ (n-1)! * 2 * (-1)^(n+1) / (log((Pi+sqrt(4+Pi^2))/2))^n. - Vaclav Kotesovec, Jan 23 2015

Mathematica

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

Crossrefs

Sequence in context: A009605 A009681 A009186 * A009346 A009367 A114249

Adjacent sequences: A009325 A009326 A009327 * A009329 A009330 A009331

Keyword

sign,easy

Author

R. H. Hardin

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Status

approved