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Number of n-node (unlabeled) connected graphs with girth 3.
5

%I #12 Aug 15 2019 16:56:34

%S 0,0,1,3,15,93,794,10850,259700,11706739,1006609723,164058686415,

%T 50335888444167,29003487017067011,31397381129017616776,

%U 63969560112658419275907,245871831682052901418048916

%N Number of n-node (unlabeled) connected graphs with girth 3.

%C Number of unlabeled, connected graphs on n vertices with at least one induced subgraph isomorphic to a K_3, where K_3 is the complete graph on three vertices (a triangle). - _Travis Hoppe_ and _Anna Petrone_, Jun 01 2014

%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 [math.CO], 2014

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

%Y a(n) = A001349(n) - A024607(n).

%Y Cf. A128041, A128042, A128236-A128243.

%K nonn

%O 1,4

%A _Keith Briggs_, May 05 2007

%E Corrected and extended by _Martin Fuller_, May 01 2015

%E Information added by _Falk Hüffner_, Nov 27 2015