Number of (unlabeled) loopless multigraphs such that the sum of the numbers of vertices and edges is n.
A265581
Number of (unlabeled) loopless multigraphs such that the sum of the numbers of vertices and edges is n.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =2a(4) =3a(5) =5a(6) =9a(7) =16a(8) =29a(9) =56a(10) =110a(11) =222a(12) =465a(13) =1003a(14) =2226a(15) =5101a(16) =12010a(17) =29062a(18) =72200a(19) =183886a(20) =479544a(21) =1279228a(22) =3486584a(23) =9699975a(24) =27520936a(25) =79563707a(26) =234204235a(27) =701458966a(28) =2136296638a(29) =6611816700
External references
- oeis: A265581