a(1) = 1, a(2) = a(1) + 1, a(3) = a(2)^2 + a(2) + 1; a(n + 1) = a(n)^n + a(n)^(n-1) + ... + a(n)^2 + a(n) + 1 = {a(n)^(n + 1)-1}/{a(n) - 1}.

A110386

a(1) = 1, a(2) = a(1) + 1, a(3) = a(2)^2 + a(2) + 1; a(n + 1) = a(n)^n + a(n)^(n-1) + ... + a(n)^2 + a(n) + 1 = {a(n)^(n + 1)-1}/{a(n) - 1}.

Terms

    a(0) =1a(1) =2a(2) =7a(3) =400a(4) =25664160401

External references