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%I #3 Mar 31 2012 13:20:12
%S 1,20,200,1600,80000,1600000,16000000,1280000000,2560000000,
%T 256000000000,2560000000000,102400000000000,1024000000000000,
%U 4096000000000000,40960000000000000,6553600000000000000
%N Denominators of partial sums of Catalan numbers scaled by powers of 1/20.
%C Numerators are given under A120786.
%F a(n)=denominator(r(n)), with the rationals r(n):=sum(C(k)/20^k,k=0..n) with C(k):=A000108(k) (Catalan numbers).
%K nonn,easy,frac
%O 0,2
%A _Wolfdieter Lang_, Jul 20 2006