Primes of the form Phi(phi(k),2), the phi(k)-th cyclotomic polynomial evaluated at 2, where phi is the Euler totient function.

A211876

Primes of the form Phi(phi(k),2), the phi(k)-th cyclotomic polynomial evaluated at 2, where phi is the Euler totient function.

Terms

    a(0) =3a(1) =5a(2) =11a(3) =13a(4) =17a(5) =241a(6) =257a(7) =331a(8) =683a(9) =5419a(10) =61681a(11) =65537a(12) =2796203a(13) =15790321a(14) =22366891a(15) =4278255361a(16) =4562284561a(17) =77158673929

External references