79159domain: NPropertiesPrimalityPrimeyesAppears in sequencesLeast number beginning with prime(n) such that every concatenation is a prime.at n=21A090508Primes which are the concatenation of a prime p and 2p+1.at n=7A168166Primes formed by concatenating k and 2k+1.at n=29A309808Prime numbersat n=7759