A012280 Expansion of e.g.f.: sech(exp(x)*log(x+1)).

1, 0, -1, -3, -6, 30, 270, 1400, -3080, -86184, -893760, -754688, 61595424, 1201314400, 5341239904, -68598744240, -2871938780672, -25391249097088, 31527888993024, 10819112145879168, 155954430765392768

Offset

0,4

Links

G. C. Greubel, Table of n, a(n) for n = 0..450

Example

E.g.f. = 1 - x^2/2! - 3*x^3/3! - 6*x^4/4! + 30*x^5/5! - ...

Mathematica

With[{nn=20}, CoefficientList[Series[Sech[Exp[x]Log[x+1]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Jan 21 2013 *)

Prog

(PARI) x='x+O('x^30); Vec(serlaplace(1/cosh(exp(x)*log(x+1)))) \\ G. C. Greubel, Oct 28 2018
(Magma) m:=30; R<x>:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!( 1/Cosh(Exp(x)*Log(x+1)) )); [Factorial(n-1)*b[n]: n in [1..m-1]]; // G. C. Greubel, Oct 28 2018

Crossrefs

Sequence in context: A088436 A088506 A061137 * A282132 A002164 A331661

Adjacent sequences: A012277 A012278 A012279 * A012281 A012282 A012283

Keyword

sign

Author

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

Extensions

Definition clarified by Harvey P. Dale, Jan 21 2013

Status

approved