a(n) = number of distinct prime divisors (taken together) of numbers of the form x^2+1 for x<=10^n.

A144848

a(n) = number of distinct prime divisors (taken together) of numbers of the form x^2+1 for x<=10^n.

Terms

    a(0) =7a(1) =70a(2) =720a(3) =7102a(4) =70780a(5) =704537a(6) =7026559a(7) =70122424a(8) =700184485a(9) =6993568566a(10) =69870544960a(11) =698175242376

External references