A013245 Expansion of e.g.f.: sech(log(x+1)-tan(x))=1-3/4!*x^4-90/6!*x^6+168/7!*x^7-4095/8!*x^8...

1, 0, 0, 0, -3, 0, -90, 168, -4095, 22176, -291564, 2834480, -31372803, 415999584, -4743336598, 72640890840, -927946226207, 15092982705088, -219492662105272, 3666238685959392, -59492414408303971

Offset

0,5

Links

Table of n, a(n) for n=0..20.

Mathematica

With[{nn=20}, CoefficientList[Series[Sech[Log[x+1]-Tan[x]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Jul 13 2024 *)

Crossrefs

Sequence in context: A009784 A276909 A276910 * A013238 A013243 A013244

Adjacent sequences: A013242 A013243 A013244 * A013246 A013247 A013248

Keyword

sign

Author

Patrick Demichel

Extensions

Definition clarified by Harvey P. Dale, Jul 13 2024

Status

approved