2008/03/04 by Mahir Bilen Can, Can, Mahir Bilen, Lex E. Renner +1
Computer Science · Mathematics · #20H20 #20M07 #Algebraic Geometry (math.AG) #Combinatorics (math.CO) #Computability, Logic, AI Algorithms #FOS: Mathematics #Mathematical Dynamics and Fractals #semigroups and automata theory
paper · pdf · doi:10.48550/arxiv.0803.0491
openalex publication_date 2008/03/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The rook monoid Rn is the finite monoid whose elements are the 0-1 matrices with at most one nonzero entry in each row and column. The group of invertible elements of Rn is isomorphic to the symmetric group Sn. The natural extension to Rn of the Bruhat-Chevalley ordering on the symmetric group is defined in \citeRenner86. In this paper, we find an efficient, combinatorial description of the Bruhat-Chevalley ordering on Rn. We also give a useful, combinatorial formula for the length function on Rn.