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arXiv · 2212.10354

Edge Contraction and Line Graphs

Hany Ibrahim·Peter Tittmann
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Abstract

Given a family of graphs $\mathcal{H}$, a graph $G$ is $\mathcal{H}$-free if any subset of $V(G)$ does not induce a subgraph of $G$ that is isomorphic to any graph in $\mathcal{H}$. We present sufficient and necessary conditions for a graph $G$ such that $G/e$ is $\mathcal{H}$-free for any edge $e$ in $E(G)$. Thereafter, we use these conditions to characterize claw-free and line graphs.

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Hany Ibrahim, Peter Tittmann. 2023-03-06. Edge Contraction and Line Graphs. https://arxiv.org/abs/2212.10354

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