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%I #18 Sep 08 2022 08:44:37
%S 1,0,0,0,12,-120,1020,-8820,82908,-867888,10145760,-131406000,
%T 1864232832,-28656815616,473108471472,-8332064722800,155724385537488,
%U -3076215029701248,64018830395437056,-1399676595110345088
%N Expansion of e.g.f. cosh(log(1+x)^2).
%H G. C. Greubel, <a href="/A009140/b009140.txt">Table of n, a(n) for n = 0..250</a>
%p seq(coeff(series(factorial(n)*cosh(log(1+x)^2), x,n+1),x,n),n=0..20); # _Muniru A Asiru_, Jul 31 2018
%t With[{nmax = 30}, CoefficientList[Series[Cosh[Log[1 + x]^2], {x, 0, nmax}], x]*Range[0, nmax]!] (* _G. C. Greubel_, Jul 30 2018 *)
%o (PARI) x='x+O('x^30); Vec(serlaplace(cosh(log(1+x)^2))) \\ _G. C. Greubel_, Jul 30 2018
%o (Magma) m:=30; R<x>:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!(Cosh(Log(1+x)^2))); [Factorial(n-1)*b[n]: n in [1..m]]; // _G. C. Greubel_, Jul 30 2018
%K sign,easy
%O 0,5
%A _R. H. Hardin_
%E Extended with signs by _Olivier Gérard_, Mar 15 1997