On the Number of Posets

This paper presents combinatorial facts dealing with the number of unlabeled partially ordered sets (posets) refined by the number of arcs in the Hasse diagram (sequence A342447 in OEIS). The main result is that the differences with respect to the number of points in this sequence become stationary if the number of points is sufficiently high. These differences are proposed as the new sequence A376894. In addition, the underlying combinatorial and graph theoretical arguments were used to extend some further OEIS sequences.