A013256 Expansion of e.g.f.: sec(log(x+1)-arctan(x))=1+3/4!*x^4-40/5!*x^5+250/6!*x^6-840/7!*x^7...

1, 0, 0, 0, 3, -40, 250, -840, 5145, -117360, 1667700, -15263600, 150117275, -2670166200, 50627578950, -785508087000, 12133753256625, -237020801836000, 5185811491549000, -108420617788236000

Offset

0,5

Links

Table of n, a(n) for n=0..19.

Mathematica

With[{nn=20}, CoefficientList[Series[Sec[Log[x+1]-ArcTan[x]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Dec 19 2022 *)

Crossrefs

Sequence in context: A013257 A013250 A013255 * A013293 A013286 A013291

Adjacent sequences: A013253 A013254 A013255 * A013257 A013258 A013259

Keyword

sign

Author

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

Extensions

Definition clarified by Harvey P. Dale, Dec 19 2022

Status

approved