login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A013330
E.g.f.: tan(exp(x)-sec(x))=x+3/3!*x^3-4/4!*x^4+37/5!*x^5-180/6!*x^6...
0
0, 1, 0, 3, -4, 37, -180, 1015, -11464, 57961, -1001640, 6231819, -117917644, 1041455053, -18546221148, 232421139007, -3887058864784, 64390950162769, -1075269065795664, 21514220038798995, -383113444907091604
OFFSET
0,4
MATHEMATICA
With[{nn=20}, CoefficientList[Series[Tan[Exp[x]-Sec[x]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Aug 21 2014 *)
CROSSREFS
Sequence in context: A102920 A064335 A376966 * A274663 A088168 A032836
KEYWORD
sign
AUTHOR
Patrick Demichel (patrick.demichel(AT)hp.com)
EXTENSIONS
Definition clarified and zero prepended by Harvey P. Dale, Aug 21 2014
STATUS
approved