a(n) = [x^n] 1/((1 - n*x) * Product_{k=0..n-1} (1 - k*x)^2).

A383883

a(n) = [x^n] 1/((1 - n*x) * Product_{k=0..n-1} (1 - k*x)^2).

Terms

    a(0) =1a(1) =1a(2) =11a(3) =222a(4) =6627a(5) =262570a(6) =12978758a(7) =769079444a(8) =53138842515

External references