a(n) = a(n-1) * (1 + a(n-1)/n^2) with a(0) = 2.

A061322

a(n) = a(n-1) * (1 + a(n-1)/n^2) with a(0) = 2.

Terms

    a(0) =2a(1) =6a(2) =15a(3) =40a(4) =140a(5) =924a(6) =24640a(7) =12415040

External references