The first nontrivial (k>n+2) palindromic prime in both bases n and n+2 or -1 if it does not exist.

A057199

The first nontrivial (k>n+2) palindromic prime in both bases n and n+2 or -1 if it does not exist.

Terms

    a(0) =5a(1) =1667a(2) =7517a(3) =34853363a(4) =116755331881a(5) =20537111057a(6) =373

External references