Numbers n such that (10^n-1)/9 is prime, but cannot be written in the form a^2 + 3*b^2.

A216549

Numbers n such that (10^n-1)/9 is prime, but cannot be written in the form a^2 + 3*b^2.

Terms

    a(0) =2a(1) =23a(2) =317a(3) =1031a(4) =86453

External references