151607domain: NPropertiesPrimalityPrimeyesAppears in sequencesPrimes p such that q = 4p^2 + 1, r = 4q^2 + 1 and s = 4r^2 + 1 are all primes.at n=3A122429Primes that are the concatenation p|q of two primes p and q with the same number of digits, where r = (p+q)/2, r|q and p|r are all primes.at n=8A358420Prime numbersat n=13989