A243781 - OEIS

A243781

Number of simple connected graphs on n nodes whose independence number a(g)=2.

%I #11 Nov 02 2017 23:08:40

%S 0,0,1,4,11,34,103,405,1892,12166

%N Number of simple connected graphs on n nodes whose independence number a(g)=2.

%C The independence number of a graph is the cardinality of the largest independent vertex set.

%H Travis Hoppe and Anna Petrone, <a href="https://github.com/thoppe/Encyclopedia-of-Finite-Graphs">Encyclopedia of Finite Graphs</a>

%H T. Hoppe and A. Petrone, <a href="http://arxiv.org/abs/1408.3644">Integer sequence discovery from small graphs</a>, arXiv preprint arXiv:1408.3644, 2014

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/IndependenceNumber.html">Independence Number</a>, <a href="http://mathworld.wolfram.com/MaximumIndependentVertexSet.html">Maximum Independent Vertex Set</a>

%Y Column 2 of A294490.

%Y Cf. Values of a(g) for simple connected graphs, A243781, A243782, A243783, A243784.

%K nonn,more

%O 1,4

%A _Travis Hoppe_ and _Anna Petrone_, Jun 20 2014