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Number of 6-chromatic (i.e., chromatic number equals 6) simple graphs on n nodes.
10

%I #15 Feb 16 2025 08:32:47

%S 0,0,0,0,0,1,6,81,2028,115391,14662562

%N Number of 6-chromatic (i.e., chromatic number equals 6) simple graphs on n nodes.

%H Keith M. Briggs, <a href="http://keithbriggs.info/cgt.html">Combinatorial Graph Theory</a>

%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/n-ChromaticGraph.html">n-Chromatic Graph</a>

%Y Column k=6 of A084268.

%Y Cf. A076278, A076279, A076280, A076281.

%K nonn,more,changed

%O 1,7

%A _Eric W. Weisstein_, Oct 06 2002

%E a(10) from _Keith Briggs_, Mar 14 2006

%E a(11) from _Michael Sollami_, Jan 28 2012