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 A198634 Number of weakly perfect graphs on n nodes. 4
 1, 2, 4, 11, 33, 152, 1006, 11805, 257542, 11011758, 917095022, 145164791300 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS A graph is weakly perfect if it has equal chromatic and clique numbers. First differs from A287007 (fractional chromatic number equals chromatic number) at a(8). - Eric W. Weisstein, May 17 2017 LINKS Table of n, a(n) for n = 1..12 F. Hüffner, tinygraph, software for generating integer sequences based on graph properties, version 4361e42 Eric Weisstein's World of Mathematics, Weakly Perfect Graph FORMULA a(n) = A287009(n) + A287023(n). CROSSREFS Cf. A287007, A287009, A287023. Sequence in context: A076316 A304125 A082104 * A287007 A369843 A099215 Adjacent sequences: A198631 A198632 A198633 * A198635 A198636 A198637 KEYWORD nonn,more AUTHOR Eric W. Weisstein, Feb 19 2013 EXTENSIONS a(10) from Eric W. Weisstein, May 17 2017 a(11) added using tinygraph by Falk Hüffner, Aug 13 2017 a(12) added using tinygraph by Jakub Jablonski, Sep 26 2020 STATUS approved

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Last modified August 8 12:42 EDT 2024. Contains 375021 sequences. (Running on oeis4.)