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A013321 E.g.f.: sech(exp(x)-cos(x)). 0
1, 0, -1, -6, -11, 80, 923, 3682, -26567, -585120, -3969849, 24427370, 948294477, 9793100720, -42570639997, -3129194240622, -45887540775759, 90022891149760, 18204741288946383, 363299569735984474 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Table of n, a(n) for n=0..19.

EXAMPLE

sech(exp(x)-cos(x)) = 1 -x^2/2! -6*x^3/3! -11*x^4/4! +80*x^5/5! ...

MATHEMATICA

With[{nn=20}, CoefficientList[Series[Sech[Exp[x]-Cos[x]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Jun 06 2015 *)

CROSSREFS

Sequence in context: A077697 A283820 A219702 * A192893 A188599 A217934

Adjacent sequences:  A013318 A013319 A013320 * A013322 A013323 A013324

KEYWORD

sign

AUTHOR

Patrick Demichel (patrick.demichel(AT)hp.com)

STATUS

approved

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Last modified December 11 13:46 EST 2017. Contains 295876 sequences.