134677domain: NPropertiesPrimalityPrimeyesAppears in sequencesNumbers k such that one of k, k+1, k+2 is prime and the other two are semiprimes, and one of R(n), R(n+1), R(n+2) is prime and the other two are semiprimes, where R = A004086.at n=28A354285Prime numbersat n=12551