Number of mixed Husimi trees with n nodes; or rooted polygonal cacti with bridges.

A000237

Number of mixed Husimi trees with n nodes; or rooted polygonal cacti with bridges.

Terms

    a(0) =0a(1) =1a(2) =1a(3) =3a(4) =8a(5) =26a(6) =84a(7) =297a(8) =1066a(9) =3976a(10) =15093a(11) =58426a(12) =229189a(13) =910127a(14) =3649165a(15) =14756491a(16) =60103220a(17) =246357081a(18) =1015406251a(19) =4205873378a(20) =17497745509a(21) =73084575666a(22) =306352303774

External references