A137861 Number of unlabeled graphs with n nodes and an odd sum of nodes and edges.

1, 1, 2, 5, 18, 78, 522, 6168, 137352, 6002584, 509498932, 82545585936, 25251015686776, 14527077828617744, 15713242984902154384, 32000507852263778595584, 122967932076766466347469888

Offset

1,3

Comments

a(n) = A054960(n) for even n and A007869(n) for odd n.

Links

Table of n, a(n) for n=1..17.

Crossrefs

Cf. A054960 Number of unlabeled graphs with n nodes and an odd number of edges. A007869 Complementary pairs of graphs on n nodes. Also unlabeled graphs with n nodes and an even number of edges.

Sequence in context: A208968 A338179 A206293 * A286282 A192637 A111916

Adjacent sequences: A137858 A137859 A137860 * A137862 A137863 A137864

Keyword

nonn

Author

Tanya Khovanova, Apr 29 2008

Status

approved