a(n) = 4^n * Sum_{k=0..n} binomial(2*k,k)^3 / 4^k.

A167869

a(n) = 4^n * Sum_{k=0..n} binomial(2*k,k)^3 / 4^k.

Terms

    a(0) =1a(1) =12a(2) =264a(3) =9056a(4) =379224a(5) =17519904a(6) =858968640a(7) =43860112128

External references