Number of connected partially ordered sets with n labeled points.

A001927

Number of connected partially ordered sets with n labeled points.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =12a(4) =146a(5) =3060a(6) =101642a(7) =5106612a(8) =377403266a(9) =40299722580

External references