A009033 Expansion of e.g.f.: cos(log(1+x)/cosh(x)).

1, 0, -1, 3, 2, -20, -160, 1470, -1412, -17208, -311900, 5526620, -27336032, 64471680, -3978938184, 91242933600, -974175281648, 9223539606848, -209919913406800, 4978659648353904, -83195760215366560, 1324088843470088640

Offset

0,4

Links

G. C. Greubel, Table of n, a(n) for n = 0..250

Mathematica

With[{nn=30}, CoefficientList[Series[Cos[Log[1+x]/Cosh[x]], {x, 0, nn}], x] Range[0, nn]!] (* Harvey P. Dale, Sep 10 2012 *)

Prog

(PARI) x='x+O('x^30); Vec(serlaplace(cos(log(1+x)/cosh(x)))) \\ G. C. Greubel, Jul 22 2018
(Magma) m:=30; R<x>:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!(Cos(Log(1+x)/Cosh(x)))); [Factorial(n-1)*b[n]: n in [1..m]]; // G. C. Greubel, Jul 22 2018

Crossrefs

Sequence in context: A123225 A009028 A009022 * A298661 A323780 A350290

Adjacent sequences: A009030 A009031 A009032 * A009034 A009035 A009036

Keyword

sign,easy

Author

R. H. Hardin

Extensions

Extended with signs by Olivier Gérard, Mar 15 1997

Definition clarified by Harvey P. Dale, Sep 10 2012

Status

approved