A132331 - OEIS

A132331

G.f.: A(x) = (A_1)^3 where A_1 = 1 + x*(A_2)^3; A_2 = 1 + x^2*(A_3)^3; A_3 = 1 + x^3*(A_4)^3; ... A_n = 1 + x^n*(A_{n+1})^3 for n>=1.

%I #5 Jan 21 2021 22:12:01

%S 1,3,3,10,18,18,72,93,141,381,423,990,1701,2304,4998,7275,12960,21195,

%T 34812,58860,90576,163603,239445,413964,669096,1017918,1768608,

%U 2639988,4383036,6880680,10911267,17411292,26930250,43797420,66324909,107180772

%N G.f.: A(x) = (A_1)^3 where A_1 = 1 + x*(A_2)^3; A_2 = 1 + x^2*(A_3)^3; A_3 = 1 + x^3*(A_4)^3; ... A_n = 1 + x^n*(A_{n+1})^3 for n>=1.

%F Self-convolution cube of A132330.

%o (PARI) {a(n)=local(A=1+x*O(x^n)); for(j=0,n-1,A=1+x^(n-j)*A^3);polcoeff(A^3,n)}

%Y Cf. A132330 (cube-root); A001764; A095830 (variant).

%K nonn

%O 0,2

%A _Paul D. Hanna_, Aug 20 2007