2842597domain: NPropertiesPrimalityPrimeyesAppears in sequencesPrimes p such that sigma(p-1)+sigma(p+1) is prime.at n=31A067464Primes p such that 28*p +- 33, 38*p +- 33 and 58*p +- 33 are all primes.at n=13A106025Prime numbersat n=206288