3300593domain: NPropertiesPrimalityPrimeyesAppears in sequencesNumbers k such that (5^k - 1)/4 is prime.at n=18A004061Start of seven consecutive primes whose digit reversals are also prime.at n=26A103169Primes that are the first in a run of exactly 7 emirps.at n=15A346027Prime numbersat n=236939