267299domain: NPropertiesPrimalityPrimeyesAppears in sequencesPrimes that remain prime through 4 iterations of function f(x) = 7x + 6.at n=21A023318Lesser of twin primes p1 such that p1^3 + p2^2 are average of twin primes. p1 and p2 twin primes, p1 < p2.at n=31A139778Prime numbersat n=23416