267271domain: NPropertiesPrimalityPrimeyesAppears in sequencesPrimes that are concatenations of k with k + 4.at n=28A032627Lucky numbers that are concatenations of n with n + 4.at n=19A032654Smallest difference > 1 between d and p/d for any divisor d of the partial product p of the sequence, starting with 7.at n=8A082121Prime numbersat n=23414