

A216783


Number of maximal trianglefree graphs with n vertices.


1



1, 1, 1, 2, 3, 4, 6, 10, 16, 31, 61, 147, 392, 1274, 5036, 25617, 164796, 1337848, 13734745, 178587364, 2911304940, 58919069858, 1474647067521, 45599075629687
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OFFSET

1,4


COMMENTS

A maximal trianglefree graph is a trianglefree graph so that the insertion of each new edge introduces a triangle. For graphs of order larger than 2 this is equivalent to being trianglefree and having diameter 2.


REFERENCES

S. Brandt, G. Brinkmann and T. Harmuth, The Generation of Maximal TriangleFree Graphs, Graphs and Combinatorics, 16 (2000), 149157.


LINKS

Table of n, a(n) for n=1..24.
S. Brandt, G. Brinkmann and T. Harmuth, MTF.
Gunnar Brinkmann, Jan Goedgebeur and J.C. SchlagePuchta, triangleramsey.
Gunnar Brinkmann, Jan Goedgebeur, and JanChristoph SchlagePuchta, Ramsey numbers R(K3,G) for graphs of order 10, arXiv 1208.0501 (2012).
Jan Goedgebeur, On minimal trianglefree 6chromatic graphs, arXiv:1707.07581 [math.CO] (2017).
House of Graphs, Maximal trianglefree graphs.


CROSSREFS

Cf. A280020 (labeled graphs).
Sequence in context: A173697 A017986 A293632 * A026502 A060163 A106511
Adjacent sequences: A216780 A216781 A216782 * A216784 A216785 A216786


KEYWORD

nonn


AUTHOR

Jan Goedgebeur, Sep 18 2012


EXTENSIONS

a(24) added by Jan Goedgebeur, Jun 05 2018


STATUS

approved



