a(1) = 13 and then the smallest prime that is obtained by placing digits on both sides of the previous term. Or smallest prime that encompasses a(n-1).

A075601

a(1) = 13 and then the smallest prime that is obtained by placing digits on both sides of the previous term. Or smallest prime that encompasses a(n-1).

Terms

    a(0) =13a(1) =2131a(2) =121313a(3) =51213137a(4) =3512131379a(5) =135121313797

External references