A319114 Number of simple toroidal graphs on n nodes.

0, 0, 0, 0, 1, 14, 222, 5365, 190590, 9419910

Offset

1,6

Comments

a(n) <= A145269(n).

a(n) = A145269(n) for n < 8.

a(8) = A145269(8) - 15 since there are 15 double-toroidal graphs on 8 nodes (all of which are connected).

Here, "toroidal graph" refers to a graph with genus = 1. - Eric W. Weisstein, Jul 02 2026

Links

Table of n, a(n) for n=1..10.

Eric Weisstein's World of Mathematics, Simple Graph.

Eric Weisstein's World of Mathematics, Toroidal Graph.

Crossrefs

Cf. A145269 (nonplanar simple graphs).

Cf. A395155 (double-toroidal graphs).

Cf. A394215 (simple graphs on n nodes with genus k).

Sequence in context: A113894 A225315 A292041 * A145269 A221582 A320762

Adjacent sequences: A319111 A319112 A319113 * A319115 A319116 A319117

Keyword

nonn,more,changed

Author

Eric W. Weisstein, Sep 10 2018

Extensions

a(9) from Eric W. Weisstein, Jul 02 2026

a(10) from Eric W. Weisstein, Jul 11 2026

Status

approved