Primes p such that sigma(2^(p+1)) is prime.
A278053
Primes p such that sigma(2^(p+1)) is prime.
Terms
- a(0) =3a(1) =5a(2) =11a(3) =17a(4) =29a(5) =59a(6) =1277a(7) =4421a(8) =110501a(9) =132047a(10) =20996009a(11) =24036581
External references
- oeis: A278053