A076315 - OEIS

%I #15 Nov 08 2022 19:17:04

%S 1,2,4,10,29,119,667,6024,88500,2109828,78347534,4383817811,

%T 362181166439

%N Number of 3-colorable (i.e., chromatic number <= 3) simple graphs on n nodes.

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

%F a(n) = A033995(n) + A076279(n). - _Andrew Howroyd_, Dec 02 2018

%Y Cf. A033995, A076279, A076316, A076317, A076318, A076319, A076320, A076321.

%K nonn,more

%O 1,2

%A _Eric W. Weisstein_, Oct 06 2002

%E a(10)-a(11) from _Andrew Howroyd_, Dec 02 2018

%E a(12) from _Brendan McKay_, Jan 19 2020

%E a(13) from _Brendan McKay_, Nov 08 2022