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%I #4 Mar 30 2012 18:37:03
%S 1,1,4,30,321,4389,72512,1399755,30865353,764755508,21024535960,
%T 634924059276,20890221475598,743727414390456,28484480606420928,
%U 1167761832049224515,51022550712426870397,2366859765773183488674
%N Main diagonal of table A128325.
%F a(n) = [x^n] {1 + H(x)}, where H(x) is the (n+2)-th self-composition of G(x) and G(x) = x + x*G(G(x)) is the g.f. of A030266.
%o (PARI) {a(n)=local(A=1+x,B);for(i=0,n,A=1+x*A*subst(A,x,x*A+x*O(x^n))); B=A;for(i=1,n,B=subst(B,x,x*A+x*O(x^n)));polcoeff(B,n)}
%Y Cf. A030266; A128325 (table), A128326 (row 1), A128327 (row 2), A128328 (row 3).
%K nonn
%O 0,3
%A _Paul D. Hanna_, Mar 11 2007
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