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Number of disconnected simple graphs on n vertices whose fractional chromatic number equals its chromatic number.
3

%I #12 May 19 2017 02:40:06

%S 0,1,2,5,13,43,186,1187,13009,270986

%N Number of disconnected simple graphs on n vertices whose fractional chromatic number equals its chromatic number.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/ChromaticNumber.html">Chromatic Number</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/FractionalChromaticNumber.html">Fractional Chromatic Number</a>

%F a(n) = A287007(n) - A243252(n).

%Y Cf. A287007 (number of not-necessarily connected simple graphs on n nodes with fractional chromatic number equal to chromatic number).

%Y Cf. A243252 (number of simple connected graphs on n node with fractional chromatic number equal to chromatic number).

%K nonn,more

%O 1,3

%A _Eric W. Weisstein_, May 17 2017