Number of labeled order relations on n nodes in which longest chain has 2 nodes.

A055531

Number of labeled order relations on n nodes in which longest chain has 2 nodes.

Terms

    a(0) =2a(1) =12a(2) =86a(3) =840a(4) =11642a(5) =227892a(6) =6285806a(7) =243593040a(8) =13262556722

External references