A286949 Number of perfect disconnected simple graphs on n nodes.

0, 1, 2, 5, 13, 43, 182, 1082, 9979, 147043, 3419289, 119265551

Offset

1,3

Links

Table of n, a(n) for n=1..12.

Eric Weisstein's World of Mathematics, Disconnected Graph

Eric Weisstein's World of Mathematics, Perfect Graph

Formula

a(n) = A052431(n) - A052433(n).

Example

\bar K_2; (1 graph)
\bar K_3, K_1 \cup K_2; (2 graphs)
\bar K_4, P_2 \cup 2 K_1, P_3 \cup K_1, C_3 \cup K_1, 2P_2 (5 graphs)
Here, \bar indicates a graph complement and \cup a (disjoint) graph union.

Crossrefs

Sequence in context: A278171 A212824 A338660 * A287023 A287008 A119533

Adjacent sequences: A286946 A286947 A286948 * A286950 A286951 A286952

Keyword

nonn,more

Author

Eric W. Weisstein, May 17 2017

Status

approved