A009652 Expansion of tan(log(1+x)/cos(x)).

0, 1, -1, 7, -24, 215, -1515, 16721, -176568, 2363165, -32662125, 521810859, -8824531056, 165050184611, -3283420714119, 70591429387077, -1610563051907280, 39183483858949049, -1007242998864835257

Offset

0,4

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Mathematica

With[{nn=20}, CoefficientList[Series[Tan[Log[1+x]/Cos[x]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Feb 05 2012 *)

Crossrefs

Sequence in context: A209342 A203117 A197791 * A012777 A074783 A286742

Adjacent sequences: A009649 A009650 A009651 * A009653 A009654 A009655

Keyword

sign,easy

Author

R. H. Hardin

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Status

approved