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A009354
Expansion of e.g.f. log(1+sinh(x))/cos(x).
1
0, 1, -1, 6, -16, 100, -481, 3640, -26216, 244560, -2364841, 26849504, -325189096, 4398704960, -63781044601, 1005854552448, -16941897363056, 305672687929600, -5855806159566961, 119006746966185472, -2553127722541494496
OFFSET
0,4
LINKS
FORMULA
a(n) ~ (n-1)! * (-1)^(n+1) / (cos(log(1+sqrt(2))) * (log(1+sqrt(2)))^n). - Vaclav Kotesovec, Jan 23 2015
MAPLE
S:= series(log(1+sinh(x))/cos(x), x, 61):
seq(coeff(S, x, j)*j!, j=0..60); # Robert Israel, Jan 04 2019
MATHEMATICA
Log[ 1+Sinh[ x ] ]/Cos[ x ]
CoefficientList[Series[Log[1 + Sinh[x]]*Sec[x], {x, 0, 20}], x] * Range[0, 20]! (* Vaclav Kotesovec, Jan 23 2015 *)
CROSSREFS
Sequence in context: A266180 A229566 A222965 * A034191 A368875 A115331
KEYWORD
sign,easy
AUTHOR
EXTENSIONS
Extended with signs by Olivier Gérard, Mar 15 1997
STATUS
approved