959941domain: NPropertiesPrimalityPrimeyesAppears in sequencesConcatenation of prime p and nextprime(p) is prime -> cycles of 3 steps possible.at n=2A036340Triangle T(n,k) read by rows of partially ordered sets ("posets") with n unlabeled nodes and k maximal elements (0 <= k <= n).at n=58A065066Prime numbersat n=75615