Number of unlabeled 7-gonal cacti having n polygons.

A054371

Number of unlabeled 7-gonal cacti having n polygons.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =4a(4) =33a(5) =300a(6) =3412a(7) =40770a(8) =518043a(9) =6830545a(10) =92909684a(11) =1295151600a(12) =18426823044a(13) =266696759064

External references