A009827 Expansion of tanh(x)*cosh(log(1+x)).

0, 1, 0, 1, -12, 56, -240, 1744, -16128, 143296, -1353600, 14972288, -183912960, 2385640960, -33085817856, 496732177408, -7978174955520, 135579928592384, -2436661138489344, 46303359719833600, -926648972098928640

Offset

0,5

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Formula

a(n) ~ n! * (-1)^(n+1) * tanh(1) / 2. - Vaclav Kotesovec, Jan 24 2015

Mathematica

With[{nn=20}, CoefficientList[Series[Tanh[x]Cosh[Log[1+x]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Dec 04 2011 *)

Crossrefs

Sequence in context: A348584 A035289 A275505 * A068418 A068414 A199316

Adjacent sequences: A009824 A009825 A009826 * A009828 A009829 A009830

Keyword

sign,easy

Author

R. H. Hardin

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Prior incomplete Mathematica program deleted by Harvey P. Dale, Dec 04 2011

Status

approved