A198634 Number of weakly perfect graphs on n nodes.

1, 2, 4, 11, 33, 152, 1006, 11805, 257542, 11011758, 917095022, 145164791300

Offset: 1

Author

Eric W. Weisstein, Feb 19 2013

Keywords

• nonn
• more

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

Crossrefs

Cf. A287007, A287009, A287023.

Formula

a(n) = A287009(n) + A287023(n).

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