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%I #3 Mar 30 2012 18:36:46
%S 1,1,3,22,287,5496,139727,4447234,170501039,7661336692,395314147319,
%T 23054541596934,1500572569678932,107886158725753318,
%U 8494969789519239340,727287072573544716489,67284371697225428990319
%N Main diagonal of triangle A108990, in which the g.f. of row n, R_n(x), satisfies: [x^k] R_{n+1}(x) = [x^k] (1 + x*R_n(x))^(n+1) for k=0..n+1.
%o (PARI) {a(n)=local(F=1+x*O(x^n));for(m=1,n,F=(1+x*F)^m);polcoeff(F,n)}
%Y Cf. A108990, A108992, A108993, A108994, A108995, A108996.
%K nonn
%O 0,3
%A _Paul D. Hanna_, Jun 15 2005