979567domain: NPropertiesPrimalityPrimeyesAppears in sequencesNumber of partitions of the set {1,2,...,n} having no blocks with all entries of the same parity.at n=13A124425a(n) = smallest prime(j) > a(n-1) such that prime(j+1) - prime(j) = 2n, a(0) = 2.at n=42A256454Prime numbersat n=77048