A009170 - OEIS

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A009170

Expansion of cosh(tanh(x))/exp(x).

1, -1, 2, -4, 0, 24, 8, -456, 192, 11264, -20480, -289664, 1837696, -3000960, -187743488, 2697206272, 22698672128, -625547980800, -3236847570944, 138214081974272, 536307107184640, -32824743592198144, -101121059849109504

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,3

LINKS

Table of n, a(n) for n=0..22.

MATHEMATICA

Cosh[ Tanh[ x ] ]/Exp[ x ]

CROSSREFS

Sequence in context: A173315 A205975 A231915 * A009625 A308024 A347281

Adjacent sequences: A009167 A009168 A009169 * A009171 A009172 A009173

KEYWORD

sign,easy

AUTHOR

R. H. Hardin

EXTENSIONS

Extended with signs by Olivier Gérard, Mar 15 1997

STATUS

approved