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A012523
sech(sinh(x)*exp(x))=1-1/2!*x^2-6/3!*x^3-23/4!*x^4-20/5!*x^5...
0
1, 0, -1, -6, -23, -20, 743, 9422, 64433, 19032, -7391889, -131529310, -1204724391, 2412614724, 343942765463, 7487171500918, 80039031954145, -547487821933904, -48046886269866657, -1195424254383765686
OFFSET
0,4
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
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
STATUS
approved