Number of connected topologies with n unlabeled nodes.

A001928

Number of connected topologies with n unlabeled nodes.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =6a(4) =21a(5) =94a(6) =512a(7) =3485a(8) =29515a(9) =314474a(10) =4255727a(11) =73831813a(12) =1653083021a(13) =47941962135

External references