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A137861 Number of unlabeled graphs with n nodes and an odd sum of nodes and edges. 0
1, 1, 2, 5, 18, 78, 522, 6168, 137352, 6002584, 509498932, 82545585936, 25251015686776, 14527077828617744, 15713242984902154384, 32000507852263778595584, 122967932076766466347469888 (list; graph; refs; listen; history; text; internal format)
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: A006848 A208968 A206293 * A286282 A192637 A111916

Adjacent sequences:  A137858 A137859 A137860 * A137862 A137863 A137864

KEYWORD

nonn

AUTHOR

Tanya Khovanova, Apr 29 2008

STATUS

approved

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Last modified March 20 05:29 EDT 2019. Contains 321344 sequences. (Running on oeis4.)