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A009420 Expansion of log(1+x)*exp(tanh(x)). 0
0, 1, 1, 2, -8, -11, -19, 846, -1896, -111, -228159, 2453010, -11353440, 173733429, -3565851587, 41759789358, -501111404080, 9579604130881, -176443305192159, 2870638703204994, -53275482352387864, 1134671091039714069 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

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

FORMULA

a(n) ~ (n-1)! * (-1)^(n+1) * exp(-tanh(1)). - Vaclav Kotesovec, Jan 23 2015

MATHEMATICA

Log[ 1+x ]*Exp[ Tanh[ x ] ]

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

CROSSREFS

Sequence in context: A056550 A074263 A295070 * A189328 A090746 A234924

Adjacent sequences:  A009417 A009418 A009419 * A009421 A009422 A009423

KEYWORD

sign,easy

AUTHOR

R. H. Hardin

EXTENSIONS

Extended with signs by Olivier Gérard, Mar 15 1997

STATUS

approved

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Last modified August 2 09:22 EDT 2021. Contains 346422 sequences. (Running on oeis4.)