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G.f. satisfies: A(x)^2 = x + A(x*A(x)^4).
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%I #9 Aug 11 2014 06:34:12

%S 1,1,3,36,691,17953,578590,22086434,970562211,48162981790,

%T 2661660956118,162076663712956,10782672104108188,778258213420732537,

%U 60580553895367923682,5059770644086584978690,451410973011659727975191,42848908650336118172791330

%N G.f. satisfies: A(x)^2 = x + A(x*A(x)^4).

%H Vaclav Kotesovec, <a href="/A241996/b241996.txt">Table of n, a(n) for n = 0..260</a>

%F a(n) ~ c * 4^n * n^(n - 1/4 + 1/8*log(2)) / (exp(n) * log(2)^n), where c = 0.2494094681962255...

%o (PARI) {a(n)=local(A=[1, 1], Ax); for(i=1, n, A=concat(A, 0); Ax=Ser(A);

%o A[#A]=Vec(1+subst(Ax, x, x*Ax^4) - Ax^2)[#A]); A[n+1]}

%o for(n=0, 30, print1(a(n), ", "))

%Y Cf. A240996 (q=2), A240999 (q=3), A241997 (q=5), A241998 (q=6), A241999 (q=7).

%K nonn

%O 0,3

%A _Vaclav Kotesovec_, Aug 11 2014