Primes which are a sandwich of numbers made of only one digit between two 3's.

A068687

Primes which are a sandwich of numbers made of only one digit between two 3's.

Terms

    a(0) =313a(1) =353a(2) =373a(3) =383a(4) =3222223a(5) =3444443a(6) =322222223a(7) =355555553

External references