On the edge-density of 4-critical graphs
نویسندگان
چکیده
Gallai conjectured that every 4-critical graph on n vertices has at least 53n − 23 edges. We prove this conjecture for 4-critical graphs in which the subgraph induced by vertices of degree 3 is connected.
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ورودعنوان ژورنال:
- Combinatorica
دوره 29 شماره
صفحات -
تاریخ انتشار 2009