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arXiv · 1103.0239

Avoiding Colored Partitions of Lengths Two and Three

Adam M. Goyt·Lara K. Pudwell
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Abstract

Pattern avoidance in the symmetric group $S_n$ has provided a number of useful connections between seemingly unrelated problems from stack-sorting to Schubert varieties. Recent work has generalized these results to $S_n\wr C_c$, the objects of which can be viewed as "colored permutations". Another body of research that has grown from the study of pattern avoidance in permutations is pattern avoidance in $Π_n$, the set of set partitions of $[n]$. Pattern avoidance in set partitions is a generalization of the well-studied notion of noncrossing partitions. Motivated by recent results in pattern avoidance in $S_n \wr C_c$ we provide a catalog of initial results for pattern avoidance in colored partitions, $Π_n \wr C_c$. We note that colored set partitions are not a completely new concept. \emph{Signed} (2-colored) set partitions appear in the work of Björner and Wachs involving the homology of partition lattices. However, we seek to study these objects in a new enumerative context.

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Adam M. Goyt, Lara K. Pudwell. 2011-08-12. Avoiding Colored Partitions of Lengths Two and Three. https://arxiv.org/abs/1103.0239

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