a(n) = (4*n+1) * (5*n+1)^(n-2) * 6^n.

A251696

a(n) = (4*n+1) * (5*n+1)^(n-2) * 6^n.

Terms

    a(0) =1a(1) =5a(2) =324a(3) =44928a(4) =9716112a(5) =2870090496

External references