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%I #8 Jan 15 2019 10:00:55
%S 1,1,3,6,21,32,174,236,1310,2609,12579,18150,150980,198821,1471346,
%T 2645433,17956158,24534384,234506155,304507520,2773986000,4315363549,
%U 36311714888,47769153478,500399410005,637747787407,6468558255893,9142971548460,88936892205131
%N G.f.: exp( Sum_{n>=1} A174462(n)*x^n/n ) where A174462(n) = Sum_{d|n} C(n,d)^2.
%C Compare to the g.f. G(x) of the Catalan numbers:
%C G(x)^2 = exp( Sum_{n>=1} A000984(n)*x^n/n ) where A000984(n) = Sum_{k=0..n} C(n,k)^2.
%H Seiichi Manyama, <a href="/A174461/b174461.txt">Table of n, a(n) for n = 0..1671</a>
%o (PARI) {a(n)=polcoeff(exp(sum(m=1,n,x^m/m*sumdiv(m,d,binomial(m,d)^2))+x*O(x^n)),n)}
%Y Cf. A174462, A110448.
%K nonn
%O 0,3
%A _Paul D. Hanna_, Apr 04 2010
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