A012881 Expansion of e.g.f.: exp(sech(x)*arcsinh(x))=1+x+1/2!*x^2-3/3!*x^3-15/4!*x^4+5/5!*x^5...

1, 1, 1, -3, -15, 5, 345, 889, -11263, -82167, 455025, 7869301, -16466703, -906141171, -746021367, 128450716913, 480286325633, -22562588189167, -150637957014303, 4955964959446253, 46203820378253425

Offset

0,4

Links

Table of n, a(n) for n=0..20.

Mathematica

With[{nn=20}, CoefficientList[Series[Exp[Sech[x]ArcSinh[x]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Jul 08 2020 *)

Crossrefs

Sequence in context: A212203 A286783 A351697 * A248031 A066832 A102777

Adjacent sequences: A012878 A012879 A012880 * A012882 A012883 A012884

Keyword

sign

Author

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

Extensions

Definition clarified by Harvey P. Dale, Jul 08 2020

Status

approved