G.f. A(x) satisfies: A(x)^2 + A(x) - 1 = Sum_{n>=0} binomial(3*n,n)^2 * x^n.
A322189
G.f. A(x) satisfies: A(x)^2 + A(x) - 1 = Sum_{n>=0} binomial(3*n,n)^2 * x^n.
Terms
- a(0) =1a(1) =3a(2) =72a(3) =2208a(4) =75531a(5) =2748957a(6) =104125542a(7) =4055630148a(8) =161248468944
External references
- oeis: A322189