Binomial coefficients: a(n) = binomial(3*n,n)^2.

A188662

Binomial coefficients: a(n) = binomial(3*n,n)^2.

Terms

    a(0) =1a(1) =9a(2) =225a(3) =7056a(4) =245025a(5) =9018009a(6) =344622096a(7) =13521038400a(8) =540917591841

External references