论文信息 - On a conjecture of Hoàng and Tu concerning perfectly orderable graphs

On a conjecture of Hoàng and Tu concerning perfectly orderable graphs

Hoang and Tu [On the perfect orderability of unions of two graphs, J. Graph Theory 33 (2000) 32-43] conjectured that a weakly triangulated graph which does not contain a chordless path with six vertices is perfectly orderable. We present a counter example to this conjecture.

Stefan Hougardy

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