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%I #7 Feb 08 2016 12:44:57
%S 1,1,4,33,436,8183,204086,6482641,254507098,12071123966,679190315310,
%T 44661150338934,3389246296048276,293668284385781381,
%U 28785799019660366614,3166449702201279923725,388125298319949129243244,52681998287784899631795504,7874555043366017438046929702,1289724117374870730134874529049
%N a(n) = A266489(n)/n, for n>=1.
%C Conjectured to consist entirely of integers.
%H Paul D. Hanna, <a href="/A268293/b268293.txt">Table of n, a(n) for n = 1..300</a>
%F The g.f. of A266489, G(x) = 1 + x*A'(x), satisfies: [x^n] G( x/G(x)^n ) = 0 for n>1.
%e G.f.: A(x) = x + x^2 + 4*x^3 + 33*x^4 + 436*x^5 + 8183*x^6 + 204086*x^7 + 6482641*x^8 + 254507098*x^9 + 12071123966*x^10 +...
%e such that G(x) = 1 + x*A'(x):
%e G(x) = 1 + x + 2*x^2 + 12*x^3 + 132*x^4 + 2180*x^5 + 49098*x^6 + 1428602*x^7 + 51861128*x^8 + 2290563882*x^9 + 120711239660*x^10 +...+ A266489(n)*x^n +...
%e satisfies: [x^n] G( x/G(x)^n ) = 0 for n>1.
%o (PARI) {a(n) = my(A=[1, 1]); for(i=2, n, A=concat(A, 0); A[#A] = -Vec(subst(Ser(A), x, x/Ser(A)^(#A-1)))[#A]); A[n+1]/n}
%o for(n=1, 30, print1(a(n), ", "))
%Y Cf. A266489.
%K nonn
%O 1,3
%A _Paul D. Hanna_, Feb 08 2016
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