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A009653 Expansion of tan(log(1+x)/cosh(x)). 1
0, 1, -1, 1, -12, 55, -255, 2679, -23632, 201245, -2409525, 30433181, -383307804, 5609915779, -89478694851, 1470425213763, -26173709472960, 501554172182201, -10043883092049993, 212501921779526329, -4764376768067195020 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..100

MATHEMATICA

With[{nn=20}, CoefficientList[Series[Tan[Log[1+x]/Cosh[x]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, May 28 2013 *)

CROSSREFS

Sequence in context: A143856 A207102 A229424 * A133001 A104188 A069552

Adjacent sequences:  A009650 A009651 A009652 * A009654 A009655 A009656

KEYWORD

sign,easy

AUTHOR

R. H. Hardin

EXTENSIONS

Extended with signs by Olivier Gérard, Mar 15 1997

Prior Mathematica program replaced by Harvey P. Dale, May 28 2013

STATUS

approved

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Last modified March 25 20:10 EDT 2019. Contains 321477 sequences. (Running on oeis4.)