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A287023
Number of simple disconnected weakly perfect graphs on n vertices.
2
0, 1, 2, 5, 13, 43, 186, 1187, 13006, 270900, 11286208
OFFSET
1,3
COMMENTS
First differs from A287008 (number of simple disconnected graphs with equal chromatic and fractional chromatic number) at a(8).
LINKS
Eric Weisstein's World of Mathematics, Disconnected Graph
Eric Weisstein's World of Mathematics, Weakly Perfect Graph
FORMULA
a(n) = A198634(n) - A287009(n).
CROSSREFS
Cf. A198634 (number of not necessarily connected simple weakly perfect graphs).
Cf. A287009 (number of not connected simple weakly perfect graphs).
Cf. A287008 (number of simple disconnected graphs with equal chromatic and fractional chromatic number).
Sequence in context: A212824 A338660 A286949 * A287008 A119533 A375730
KEYWORD
nonn,more
AUTHOR
Eric W. Weisstein, May 18 2017
EXTENSIONS
a(11) from formula by Falk Hüffner, Aug 13 2017
STATUS
approved