A009097 - OEIS

%I #23 Sep 08 2022 08:44:37

%S 1,0,-2,3,-3,10,-56,315,-1971,13788,-105246,857615,-7266223,61296222,

%T -465353292,1982748495,36246192441,-1600097656520,43901543199046,

%U -1078930450441413,25757481055625541,-615789512284527630

%N Expansion of e.g.f. cos(x)*cos(log(1+x)).

%H Vincenzo Librandi, <a href="/A009097/b009097.txt">Table of n, a(n) for n = 0..100</a>

%t With[{nn=30},CoefficientList[Series[Cos[x]*Cos[Log[1+x]],{x,0,nn}],x] Range[0,nn]!] (* _Harvey P. Dale_, Jun 24 2014 *)

%o (PARI) x='x+O('x^30); Vec(serlaplace(cos(x)*cos(log(1+x)))) \\ _G. C. Greubel_, Jul 26 2018

%o (Magma) m:=30; R<x>:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!(Cos(x)*Cos(Log(1+x)))); [Factorial(n-1)*b[n]: n in [1..m]]; // _G. C. Greubel_, Jul 26 2018

%K sign,easy

%O 0,3

%A _R. H. Hardin_

%E Extended with signs by _Olivier Gérard_, Mar 15 1997

%E Prior Mathematica program replaced by _Harvey P. Dale_, Jun 24 2014