A013256 - OEIS

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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

(list; graph; refs; listen; history; text; internal format)

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