a(n) = 3^n * n! * binomial(5*n/3,n) * Sum_{k=1..n} 1/(2*n+3*k).

A384170

a(n) = 3^n * n! * binomial(5*n/3,n) * Sum_{k=1..n} 1/(2*n+3*k).

Terms

    a(0) =1a(1) =17a(2) =423a(3) =14198a(4) =603194a(5) =31069980a(6) =1882538440a(7) =131223122480

External references