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arXiv · 1212.1943

Injective Labeled Oriented Trees are Aspherical

Jens Harlander·Stephan Rosebrock
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Abstract

A labeled oriented tree is called injective if each generator occurs at most once as an edge label. We show that injective labeled oriented trees are aspherical. The proof relies on a new relative asphericity test based on a lemma of Stallings.

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Jens Harlander, Stephan Rosebrock. 2016-11-04. Injective Labeled Oriented Trees are Aspherical. https://arxiv.org/abs/1212.1943

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