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A009378 Expansion of log(1+tan(x)*sinh(x)). 1
0, 2, 0, 22, 280, 5402, 515460, 11703382, 2688141040, 146635350962, 34251754225020, 4629204580980142, 993794187704175400, 265705552906954222922, 63184407507496166760180 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..14.

FORMULA

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

MATHEMATICA

Log[ 1+Tan[ x ]*Sinh[ x ] ] (* Even Part *)

nn = 20; Table[(CoefficientList[Series[Log[1 + Sinh[x]*Tan[x]], {x, 0, 2*nn}], x] * Range[0, 2*nn]!)[[n]], {n, 1, 2*nn+1, 2}] (* Vaclav Kotesovec, Jan 23 2015 *)

CROSSREFS

Sequence in context: A282134 A293938 A254042 * A106708 A138551 A133490

Adjacent sequences:  A009375 A009376 A009377 * A009379 A009380 A009381

KEYWORD

nonn

AUTHOR

R. H. Hardin

EXTENSIONS

Extended and signs tested by Olivier Gérard, Mar 15 1997

STATUS

approved

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Last modified December 5 03:03 EST 2021. Contains 349530 sequences. (Running on oeis4.)