3 citations · 6 across the 4 of their papers we have counts for
4 papers
What Could Be a Simple Permutation?
Rehana Ashraf, Barbu Berceanu, Ayesha Riasat
Different ways to describe a permutation, as a sequence of integers, or a product of Coxeter generators, or a tree, give different choices to define a simple permutation. We recoll…
Fibonacci numbers and positive braids
Rehana Ashraf, Barbu Berceanu, Ayesha Riasat
The paper contains enumerative combinatorics for positive braids, square free braids, and simple braids, emphasizing connections with classical Fibonacci sequence. The simple subgr…
Simple Braids
Rehana Ashraf, Barbu Berceanu
We study a subset of square free positive braids and we give a few algebraic characterizations of them and one geometric characterization: the set of positive braids whose closures…
Recurrence relation for HOMFLY polynomial and rational specializations
Rehana Ashraf, Barbu Berceanu
Turning the skein relation for HOMFLY into a Fibonacci recurrence, we prove that there are only three rational specializations of HOMFLY polynomial: Alexander-Conway, Jones, and a…