156491domain: NPropertiesPrimalityPrimeyesAppears in sequencesPrimes p such that p and p+2 are twin primes and also the strings 987654321p and 987654321p+2 are twin primes.at n=29A103818Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 110-100-111 pattern in any orientation.at n=14A146177Prime numbersat n=14393