A012523 - OEIS

A012523

sech(sinh(x)*exp(x))=1-1/2!*x^2-6/3!*x^3-23/4!*x^4-20/5!*x^5...

1, 0, -1, -6, -23, -20, 743, 9422, 64433, 19032, -7391889, -131529310, -1204724391, 2412614724, 343942765463, 7487171500918, 80039031954145, -547487821933904, -48046886269866657, -1195424254383765686

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OFFSET

0,4

LINKS

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

MATHEMATICA

With[{nn=20}, CoefficientList[Series[Sech[Sinh[x]Exp[x]], {x, 0, nn}], x]Range[0, nn]!] (* Harvey P. Dale, Dec 15 2012 *)

CROSSREFS

Sequence in context: A154079 A160633 A012327 * A154817 A279797 A229486

Adjacent sequences: A012520 A012521 A012522 * A012524 A012525 A012526

KEYWORD

sign

AUTHOR

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

STATUS

approved