139948901domain: NPropertiesPrimalityPrimeyesAppears in sequencesSophie Germain primes of A144571.at n=7A154505Primes of the form n^2 + 1 such that (n - 1)^2 + 1 and (n + 1)^2 + 1 are semiprimes.at n=25A234693Prime numbersat n=7909471