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A009669 Expansion of tan(sin(x))/cosh(x). 0
1, -2, 12, -296, 8208, -317088, 22384832, -1922265216, 200049877248, -28532108907008, 4916900759571456, -987493645187344384, 241526023834975735808, -69201642972421758361600 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..13.

MATHEMATICA

With[{nn=30}, Take[CoefficientList[Series[Tan[Sin[x]]/Cosh[x], {x, 0, nn}], x] Range[0, nn-1]!, {2, -1, 2}]] (* Harvey P. Dale, Jun 08 2018 *)

CROSSREFS

Sequence in context: A008338 A000178 A108395 * A202729 A012380 A012377

Adjacent sequences: A009666 A009667 A009668 * A009670 A009671 A009672

KEYWORD

sign

AUTHOR

R. H. Hardin

EXTENSIONS

Extended with signs by Olivier Gérard, Mar 15 1997

Previous Mathematica program replaced by Harvey P. Dale, Jun 08 2018

STATUS

approved

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Last modified November 29 18:13 EST 2022. Contains 358431 sequences. (Running on oeis4.)