a(n) = C(2n,n) * (5^n/n!^2) * Product_{k=0..n-1} (5k+1)*(5k+4).

A184892

a(n) = C(2n,n) * (5^n/n!^2) * Product_{k=0..n-1} (5k+1)*(5k+4).

Terms

    a(0) =1a(1) =40a(2) =8100a(3) =2310000a(4) =768075000a(5) =278719056000

External references