a(n) = a(n-1)^2 + 1 for n >= 1, with a(0) = 0.

A003095

a(n) = a(n-1)^2 + 1 for n >= 1, with a(0) = 0.

Terms

    a(0) =0a(1) =1a(2) =2a(3) =5a(4) =26a(5) =677a(6) =458330a(7) =210066388901

External references