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A287008
Number of disconnected simple graphs on n vertices whose fractional chromatic number equals its chromatic number.
3
0, 1, 2, 5, 13, 43, 186, 1187, 13009, 270986
OFFSET
1,3
LINKS
Eric Weisstein's World of Mathematics, Chromatic Number
Eric Weisstein's World of Mathematics, Fractional Chromatic Number
FORMULA
a(n) = A287007(n) - A243252(n).
CROSSREFS
Cf. A287007 (number of not-necessarily connected simple graphs on n nodes with fractional chromatic number equal to chromatic number).
Cf. A243252 (number of simple connected graphs on n node with fractional chromatic number equal to chromatic number).
Sequence in context: A338660 A286949 A287023 * A119533 A375730 A066740
KEYWORD
nonn,more
AUTHOR
Eric W. Weisstein, May 17 2017
STATUS
approved