A009738 Expansion of e.g.f.: tan(x)*exp(tanh(x)).

0, 1, 2, 5, 4, 1, 38, 797, 3144, 1345, -49526, 785685, 10349516, 33807489, -460714706, 492925869, 91894143376, 846642059905, -6277401116142, -79077949115227, 1574511126111380, 36210294463841281, -81923064774031562

Offset

0,3

Links

Table of n, a(n) for n=0..22.

Mathematica

With[{nn=30}, CoefficientList[Series[Tan[x]*Exp[Tanh[x]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Feb 20 2020 *)

Crossrefs

Sequence in context: A231890 A087561 A309771 * A268647 A177067 A055127

Adjacent sequences: A009735 A009736 A009737 * A009739 A009740 A009741

Keyword

sign,easy

Author

R. H. Hardin

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Prior Mathematica program replaced and definition clarified by Harvey P. Dale, Feb 20 2020

Status

approved