Number of rooted toroidal maps with 2 faces, n vertices and no isthmuses.

Terms

a(0) =10a(1) =79a(2) =340a(3) =1071a(4) =2772a(5) =6258a(6) =12768a(7) =24090a(8) =42702a(9) =71929a(10) =116116a(11) =180817a(12) =273000a(13) =401268a(14) =576096a(15) =810084a(16) =1118226a(17) =1518195a(18) =2030644a(19) =2679523a(20) =3492412a(21) =4500870a(22) =5740800a(23) =7252830a(24) =9082710a(25) =11281725a(26) =13907124a(27) =17022565a(28) =20698576a(29) =25013032