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%I #20 Dec 17 2024 03:27:59
%S 1,2,8,63,958,27554,1457047,137144754,22249524024,6032417530135,
%T 2663111111716110,1876540387225350958
%N Number of labeled 3-colorable (i.e., chromatic number <= 3) graphs on n nodes.
%H Steven R. Finch, <a href="http://www.people.fas.harvard.edu/~sfinch/">Bipartite, k-colorable and k-colored graphs</a>
%H Steven R. Finch, <a href="/A191371/a191371.pdf">Bipartite, k-colorable and k-colored graphs</a>, June 5, 2003. [Cached copy, with permission of the author]
%H F. Hüffner, <a href="https://github.com/falk-hueffner/tinygraph">tinygraph</a>, software for generating integer sequences based on graph properties, version 8c665c7
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/n-ColorableGraph.html">n-Colorable Graph</a>
%Y Cf. A047864, A084280, A084281, A084282.
%K nonn,more
%O 1,2
%A _Eric W. Weisstein_, May 25 2003
%E a(7)-a(12) added using tinygraph by _Falk Hüffner_, Jun 20 2018