43944974

Appears in sequences

• Number of connected partially ordered sets with n unlabeled elements.at n=11A000608
• Number of prime unlabeled connected T_0 topologies (i.e., prime T_0 connected homeomorphism classes) on n points.at n=9A028858
• Triangle read by rows: T(n,k) (n>=1, k>=1) is the number of posets with n elements whose Hasse diagram has k connected components.at n=55A263864