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A009032 Expansion of cos(log(1+x)/cos(x)). 1
1, 0, -1, 3, -22, 100, -700, 3990, -28628, 171288, -1025420, 1661660, 78215392, -2266954560, 46180065256, -873515610240, 16163533621648, -300558671466048, 5688054655288496, -109993409199908496, 2184633395323803360 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

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

MATHEMATICA

With[{nmax = 30}, CoefficientList[Series[Cos[Log[1 + x]/Cos[x]], {x, 0, nmax}], x]*Range[0, nmax]!] (* G. C. Greubel, Jul 22 2018 *)

PROG

(PARI) x='x+O('x^30); Vec(serlaplace(cos(log(1+x)/cos(x)))) \\ G. C. Greubel, Jul 22 2018

(MAGMA) m:=30; R<x>:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!(Cos(Log(1+x)/Cos(x)))); [Factorial(n-1)*b[n]: n in [1..m]]; // G. C. Greubel, Jul 22 2018

CROSSREFS

Sequence in context: A095663 A254332 A009029 * A221543 A309000 A061182

Adjacent sequences:  A009029 A009030 A009031 * A009033 A009034 A009035

KEYWORD

sign,easy

AUTHOR

R. H. Hardin

EXTENSIONS

Extended with signs by Olivier Gérard, Mar 15 1997

STATUS

approved

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Last modified September 28 02:36 EDT 2020. Contains 337392 sequences. (Running on oeis4.)