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Self-convolution cube of A073711.
3

%I #9 Dec 21 2012 18:40:06

%S 1,3,6,13,21,36,58,93,141,203,306,420,616,828,1188,1569,2181,2877,

%T 3878,5085,6651,8844,11148,14928,18196,24864,29118,40540,45858,65280,

%U 70884,103425,108357,161853,162852,250395,242963,382644,356970,579637

%N Self-convolution cube of A073711.

%C The g.f. G(x) of A073711 satisfies: G(x) = G(x^2) + x*G(x^2)^2.

%H Paul D. Hanna, <a href="/A194279/b194279.txt">Table of n, a(n) for n = 0..10000</a>

%F a(n) = A073711(4*n+3)/2.

%F a(n) = A073712(2*n+1)/2, where A073712 equals the self-convolution of A073711.

%o (PARI) {a(n)=local(A=1); for(i=0, #binary(n), A=subst(A, x, x^2+x*O(x^n))+x*subst(A, x, x^2+x*O(x^n))^2); polcoeff(A^3, n)}

%o for(n=0, 65, print1(a(n), ", "))

%Y Cf. A073711, A073712.

%K nonn

%O 0,2

%A _Paul D. Hanna_, Dec 21 2012