Large induced forests in planar graphs with girth 4 or 5
نویسندگان
چکیده
We give here some new lower bounds on the order of a largest induced forest in planar graphs with girth 4 and 5. In particular we prove that a triangle-free planar graph of order n admits an induced forest of order at least 6n+7 11 , improving the lower bound of Salavatipour [M. R. Salavatipour, Large induced forests in trianglefree planar graphs, Graphs and Combinatorics, 22:113–126, 2006]. We also prove that a planar graph of order n and girth at least 5 admits an induced forest of order at least 44n+50 69 .
منابع مشابه
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عنوان ژورنال:
- CoRR
دوره abs/1409.1348 شماره
صفحات -
تاریخ انتشار 2014