179107domain: NPropertiesPrimalityPrimeyesAppears in sequencesPrimes n of the form 1000p+q with primes p and q, 998>p>q>100.at n=20A228268Primes p for which p + 4, p^2 + 4 and p^3 + 4 are primes.at n=27A243734Smallest number requiring n 1's to build using +, * and -.at n=38A255641Prime numbersat n=16258