On the Rank of Monoids of Endomorphisms of a Finite Directed Path

Abstract

In this paper we consider endomorphisms of a finite directed path from monoid generators perspective. Our main aim is to determine the rank of the monoid $\wEnd\vec{P}_n$ of all weak endomorphisms of a directed path with $n$ vertices, which is a submonoid of the widely studied monoid $\On$ of all order-preserving transformations of a $n$-chain. Also, we describe the regular elements of $\wEnd\vec{P}_n$ and calculate its size and number of idempotents.