Automorphisms of endomorphism semigroups of reflexive digraphs

被引:4
作者
Araujo, Joao [1 ]
Dobson, Edward [2 ]
Konieczny, Janusz [3 ]
机构
[1] Univ Lisbon, Ctr Algebra, P-1649003 Lisbon, Portugal
[2] Mississippi State Univ, Dept Math & Stat, Mississippi State, MS 39762 USA
[3] Univ Mary Washington, Dept Math, Fredericksburg, VA 22401 USA
关键词
Reflexive digraphs; circulant digraphs; endomorphism semigroups; automorphisms; CIRCULANT GRAPHS; ISOMORPHISM-PROBLEM; MONOIDS; ORDER;
D O I
10.1002/mana.200710033
中图分类号
O1 [数学];
学科分类号
0701 ; 070101 ;
摘要
A reflexive digraph is a pair (X, rho), where X is an arbitrary set and rho is a reflexive binary relation on X. Let End (X, rho) be the semigroup of endomorphisms of (X, rho). We determine the group of automorphisms of End(X, rho) for: digraphs containing an edge not contained in a cycle, digraphs consisting of arbitrary unions of cycles such that cycles of length >= 2 are pairwise disjoint, and some circulant digraphs. (C) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
引用
收藏
页码:939 / 964
页数:26
相关论文
共 33 条