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arXiv · 1409.1348

Large induced forests in planar graphs with girth 4 or 5

François Dross·Mickael Montassier·Alexandre Pinlou
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Abstract

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 $\frac{6n+7}{11}$ , improving the lower bound of Salavatipour [M. R. Salavatipour, Large induced forests in triangle-free 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 $\frac{44n+50}{69}$.

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François Dross, Mickael Montassier, Alexandre Pinlou. 2014-09-04. Large induced forests in planar graphs with girth 4 or 5. https://arxiv.org/abs/1409.1348

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