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arXiv · 1409.3165

Wilf-classification of mesh patterns of short length

Ísak Hilmarsson·Ingibjörg Jónsdóttir·Steinunn Sigurðardóttir·Lína Viðarsdóttir·Henning Ulfarsson
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Abstract

This paper starts the Wilf-classification of mesh patterns of length 2. Although there are initially 1024 patterns to consider we introduce automatic methods to reduce the number of potentially different Wilf-classes to at most 65. By enumerating some of the remaining classes we bring that upper-bound further down to 56. Finally, we conjecture that the actual number of Wilf-classes of mesh patterns of length 2 is 46.

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Ísak Hilmarsson, Ingibjörg Jónsdóttir, Steinunn Sigurðardóttir, Lína Viðarsdóttir, Henning Ulfarsson. 2015-10-15. Wilf-classification of mesh patterns of short length. https://arxiv.org/abs/1409.3165

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