We present a library for graph theory in Coq/Ssreflect. This library covers various notions on simple graphs, directed graphs, and multigraphs. We use it to formalize several results from the literature: Menger’s theorem, the excluded-minor characterization of treewidth-two graphs, and a correspondence between multigraphs of treewidth at most two and terms of certain algebras.

中文翻译：

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Coq 中的图论：次要、树宽和同构

我们在 Coq/Ssreflect 中提供了一个图论库。该库涵盖了关于简单图、有向图和多重图的各种概念。我们用它来形式化文献中的几个结果：门格尔定理、树宽二图的排除次要特征，以及树宽至多为二的多重图与某些代数的项之间的对应关系。