Number of rooted polyhedral graphs with n edges.

Terms

a(0) =1a(1) =0a(2) =4a(3) =6a(4) =24a(5) =66a(6) =214a(7) =676a(8) =2209a(9) =7296a(10) =24460a(11) =82926a(12) =284068a(13) =981882a(14) =3421318a(15) =12007554a(16) =42416488a(17) =150718770a(18) =538421590a(19) =1932856590a(20) =6969847486a(21) =25237057110a(22) =91729488354a(23) =334589415276