A013293 - OEIS

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A013293

E.g.f.: sech(log(x+1)-tanh(x))=1-3/4!*x^4+40/5!*x^5-250/6!*x^6+1008/7!*x^7...

1, 0, 0, 0, -3, 40, -250, 1008, -5887, 56880, -263724, -1848000, 36228093, -377490984, 7141572490, -132772794000, 1495810787297, -10978685025568, 115616765332680, -1113424428155904, -36631866029794659

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

OFFSET

0,5

LINKS

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

MATHEMATICA

With[{nn=30}, CoefficientList[Series[Sech[Log[x+1]-Tanh[x]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Dec 01 2013 *)

CROSSREFS

Sequence in context: A013250 A013255 A013256 * A013286 A013291 A013292

Adjacent sequences: A013290 A013291 A013292 * A013294 A013295 A013296

KEYWORD

sign

AUTHOR

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

EXTENSIONS

Definition clarified by Harvey P. Dale, Dec 01 2013

STATUS

approved