a(0) = 1, a(1) = 5; for n > 1, a(n) = 6*n*a(n-1) + Sum_{k=1..n-2} a(k)*a(n-k-1).

A062980

a(0) = 1, a(1) = 5; for n > 1, a(n) = 6*n*a(n-1) + Sum_{k=1..n-2} a(k)*a(n-k-1).

Terms

    a(0) =1a(1) =5a(2) =60a(3) =1105a(4) =27120a(5) =828250a(6) =30220800a(7) =1282031525a(8) =61999046400

External references