A Remark on Total Domination Critical Graphs

نویسنده

  • N. Jafari
چکیده

A graph G with no isolated vertex is total domination vertex critical if for any vertex v of G that is not adjacent to a vertex of degree one, the total domination number of G− v is less than the total domination number of G. We call these graphs γt-critical. In this paper, we disprove a conjecture posed in a recent paper(On an open problem concerning total domination critical graphs, Expo. Math. 25 (2007), 175-179). Mathematics Subject Classification: 05C69.

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تاریخ انتشار 2008