2 papers
math.CO2001
Explicit Enumeration of 321,Hexagon-Avoiding Permutations
Zvezdelina Stankova-Frenkel, Julian West
The 321,hexagon-avoiding (321-hex) permutations were introduced and studied by Billey and Warrington in as a class of elements of S_n whose Kazhdan-Lusztig and Poincare polynomials…
math.CO2001
A New Class of Wilf-Equivalent Permutations
Zvezdelina Stankova-Frenkel, Julian West
For about 10 years, the classification of permutation patterns was thought completed up to length 6. In this paper, we establish a new class of Wilf-equivalent permutation patterns…