Аннотация:
We prove that varieties of $(\ell r, rr)$-dibands and $(\ell n, rn)$-dibands coincide and describe the structure of free $(\ell r, rr)$-dibands. We also show that operations of an idempotent dimonoid with left (right) regular bands coincide, construct a new class of dimonoids and for such dimonoids give an example of a semiretraction.
Ключевые слова:
left (right) regular band, $(\ell r, rr)$-diband, diband of subdimonoids, dimonoid, semigroup.
Полный текст:
PDF файл (164 kB)