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

A368537

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

Terms

    a(0) =0a(1) =1a(2) =18a(3) =309a(4) =5828a(5) =123230a(6) =2913126a(7) =76405854a(8) =2205340936a(9) =69523722855

External references