a(n) = Sum_{k=0..n} k*C(n,k)^3*C(n+k,k), where C := binomial.

A112036

a(n) = Sum_{k=0..n} k*C(n,k)^3*C(n+k,k), where C := binomial.

Terms

    a(0) =0a(1) =2a(2) =36a(3) =708a(4) =13800a(5) =275010a(6) =5546016a(7) =112928648a(8) =2316836304a(9) =47818490310a(10) =991809240180

External references