Epigroups whose subepigroup lattice is lower semimodular
نویسندگان
چکیده
منابع مشابه
On semigroups with lower semimodular lattice of subsemigroups
The question of which semigroups have lower semimodular lattice of subsemigroups has been open since the early 1960’s, when the corresponding question was answered for modularity and for upper semimodularity. We provide a characterization of such semigroups in the language of principal factors. Since it is easily seen (and has long been known) that semigroups for which Green’s relation J is tri...
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ژورنال
عنوان ژورنال: Semigroup Forum
سال: 2012
ISSN: 0037-1912,1432-2137
DOI: 10.1007/s00233-012-9416-0