A Wilf class composed of 19 symmetry classes of quadruples of 4-letter patterns

Talha Arıkan, Emrah Kılıç and Toufik Mansour
Notes on Number Theory and Discrete Mathematics, ISSN 1310–5132
Volume 23, 2017, Number 3, Pages 123–132
Full paper (PDF, 154 Kb)

Details

Authors and affiliations

Talha Arıkan
Department of Mathematics, Hacettepe University
Ankara, Turkey

Emrah Kılıç
Department of Mathematics, TOBB Economy and Technology University
06560, Ankara, Turkey

Toufik Mansour
Department of Mathematics, University of Haifa
3498838 Haifa, Israel

Abstract

In this paper, we make a contribution to the enumeration of permutations avoiding a quadruples of 4-letter patterns by establishing a Wilf class composed of 19 symmetry classes.

Keywords

• Pattern avoidance
• Wilf-equivalence

AMS Classification

• 05A05
• 05A15

References

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