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arXiv · 1705.03638

Shuffles of trees

Eric Hoffbeck·Ieke Moerdijk
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Abstract

We discuss a notion of shuffle for trees which extends the usual notion of a shuffle for two natural numbers. We give several equivalent descriptions, and prove some algebraic and combinatorial properties. In addition, we characterize shuffles in terms of open sets in a topological space associated to a pair of trees. Our notion of shuffle is motivated by the theory of operads and occurs in the theory of dendroidal sets, but our presentation is independent and entirely self-contained.

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Eric Hoffbeck, Ieke Moerdijk. 2017-05-10. Shuffles of trees. https://arxiv.org/abs/1705.03638

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