A009765 Expansion of tan(x/cos(x)).

1, 5, 101, 4689, 381769, 47849053, 8532452397, 2051184222377, 639121206054545, 250473754883360181, 120568689462321176053, 69926680208791530760705, 48091629862193464534126041

Offset: 0

Author

R. H. Hardin

Keywords

• nonn

Programs

Mathematica

With[{nn=30},Take[CoefficientList[Series[Tan[x/Cos[x]],{x,0,nn}],x] Range[0,nn-1]!,{2,-1,2}]] (* Harvey P. Dale, Jan 06 2012 *)

Extensions

Extended and signs tested Mar 15 1997 by Olivier Gérard.