On a theorem of Sewell and Trotter
نویسندگان
چکیده
Sewell and Trotter proved that every connected α-critical graph that is not isomorphic to K1,K2 or an odd cycle contains a totally odd K4-subdivision. Their theorem implies an interesting min-max relation for stable sets in graphs without totally odd K4-subdivisions. In this note, we give a simpler proof of Sewell and Trotter’s theorem.
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عنوان ژورنال:
- Eur. J. Comb.
دوره 30 شماره
صفحات -
تاریخ انتشار 2009