313111313domain: NPropertiesPrimalityPrimeyesAppears in sequencesPalindromic primes made of only two digits say a and b such that replacing a with b and vice versa one gets another prime.at n=6A088288Successive generations of a Kolakoski(3,1) rule starting with 1 (see A066983).at n=5A111091Prime numbersat n=16923559