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Denominator of the coefficient of x^n in log(-log(1-x)/x).
8

%I #18 Sep 08 2022 08:45:07

%S 2,24,8,2880,288,362880,17280,29030400,89600,958003200,17418240,

%T 31384184832000,402361344000,62768369664000,295206912,

%U 512189896458240000,342372925440000,919636959090769920000,5377993912811520000,674400436666564608000000,89903156428800000

%N Denominator of the coefficient of x^n in log(-log(1-x)/x).

%H Robert Israel, <a href="/A075267/b075267.txt">Table of n, a(n) for n = 1..443</a>

%p S:= series(log(-log(1-x)/x),x,51):

%p seq(denom(coeff(S,x,j)),j=1..50); # _Robert Israel_, May 17 2016

%t Denominator[ CoefficientList[ Series[ Log[ -Log[1 - x]/x], {x, 0, 18}], x]]

%o (Magma) m:=25; R<x>:=PowerSeriesRing(Rationals(), m); b:=Coefficients(R!( Log(-Log(1-x)/x) )); [Denominator(b[n]): n in [1..m-2]]; // _G. C. Greubel_, Oct 29 2018

%Y Cf. A075266, A075264, A053657.

%K frac,nonn

%O 1,1

%A _Paul D. Hanna_, Sep 15 2002

%E Edited by _Robert G. Wilson v_, Sep 17 2002