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%I #6 Aug 29 2016 00:17:51
%S 0,0,1,1,3,7,11,7,15,15,23,31,47,71,191,95,191,255,575,511,767,767,
%T 1023,1151,1151,1727,1535,1535,4095,4095,5119,2047,6143,12287,12287,
%U 8191,12287,12287,24575,24575,36863,98303,131071,147455
%N Number of proper divisors of the Catalan number A000108(n).
%H G. C. Greubel, <a href="/A153788/b153788.txt">Table of n, a(n) for n = 0..1000</a>
%F a(n) = A032741(A000108(n)) = A152763(n) - 1.
%t DivisorSigma[0, CatalanNumber@Range[0, 1000]] - 1 (* _G. C. Greubel_, Aug 28 2016 *)
%o (PARI) a(n)=numdiv(binomial(2*n,n)/(n+1)) - 1 \\ _Charles R Greathouse IV_, Aug 29 2016
%Y Cf. A000108, A032741, A152762, A152763, A152988.
%K nonn
%O 0,5
%A _Omar E. Pol_, Jan 18 2009
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