A013327 Expansion of e.g.f.: exp(exp(x)-sec(x))=1+x+1/2!*x^2+2/3!*x^3+1/4!*x^4-8/5!*x^5...

1, 1, 1, 2, 1, -8, -83, -572, -3447, -21672, -123111, -737240, -3483619, -13031484, 70815357, 2064032844, 35771746481, 493920403632, 6641490804273, 85856649793936, 1103675761610485, 14215393325698588

Offset

0,4

Links

Table of n, a(n) for n=0..21.

Mathematica

With[{nn=30}, CoefficientList[Series[Exp[Exp[x]-Sec[x]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Dec 20 2015 *)

Crossrefs

Sequence in context: A333469 A239444 A224090 * A359625 A009349 A334254

Adjacent sequences: A013324 A013325 A013326 * A013328 A013329 A013330

Keyword

sign

Author

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

Extensions

Definition clarified by Harvey P. Dale, Dec 20 2015

Status

approved