Turkish Journal of Analysis and Number Theory. 2017, 5(6), 210-225
DOI: 10.12691/tjant-5-6-3
Open AccessArticle
David Callan1 and Toufik Mansour2,
1Department of Statistics, University of Wisconsin, Madison, WI
2Department of Mathematics, University of Haifa, Haifa, Israel
Pub. Date: November 03, 2017
Cite this paper:
David Callan and Toufik Mansour. Enumeration of 2-Wilf Classes of Four 4-letter Patterns. Turkish Journal of Analysis and Number Theory. 2017; 5(6):210-225. doi: 10.12691/tjant-5-6-3
Abstract
Let Sn be the symmetric group of all permutations of n letters. We show that there are precisely 64 Wilf classes consisting of exactly 2 symmetry classes of subsets of four 4-letter patterns.Keywords:
pattern avoidance Wilf-equivalence
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