Weakly graded (3+1)-free partially ordered sets (posets) on n labeled vertices.

A222865

Weakly graded (3+1)-free partially ordered sets (posets) on n labeled vertices.

Terms

    a(0) =1a(1) =1a(2) =3a(3) =19a(4) =195a(5) =2551a(6) =41343a(7) =826939a(8) =20616795a(9) =658486351a(10) =28264985223

External references