The structure of commutative ideal semigroups.
The tame degree and related invariants of non-unique factorizations
Local tameness and the finiteness of the catenary degree are two crucial finiteness conditions in the theory of non-unique factorizations in monoids and integral domains. In this note, we refine the notion of local tameness and relate the resulting invariants with the usual tame degree and the -invariant. Finally we present a simple monoid which fails to be locally tame and yet has nice factorization properties.
The theory of characters of commutative Hausdorff bicompact semigroups
The translational degree of a semigroup.
Tolerance distributive and tolerance modular varieties of commutative semigroups
Trees in commtative nil-semigroups of index two
Über das Zutreffen einer Eigenschaft einer Menge auf die Elemente der Potenzmenge
Un théorème sur les demi-groupes compacts commutatifs
Upper semicomplements and a definable element in the lattice of groupoid varieties
Valuations of lines
We enlarge the problem of valuations of triads on so called lines. A line in an -structure (it means that is a semigroup and is an automorphism or an antiautomorphism on such that ) is, generally, a sequence , , (where is the class of finite integers) of substructures of such that holds for each . We denote this line as and we say that a mapping is a valuation of the line in a line if it is, for each , a valuation of the triad in . Some theorems on an existence of...
Varieties of operator semigroups representing partitions.
Weierstrass Points with First Non-Gap Four on a Double Covering of a Hyperelliptic Curve
2000 Mathematics Subject Classification: Primary 14H55; Secondary 14H30, 14H40, 20M14.Let H be a 4-semigroup, i.e., a numerical semigroup whose minimum positive element is four. We denote by 4r(H) + 2 the minimum element of H which is congruent to 2 modulo 4. If the genus g of H is larger than 3r(H) − 1, then there is a cyclic covering π : C −→ P^1 of curves with degree 4 and its ramification point P such that the Weierstrass semigroup H(P) of P is H (Komeda [1]). In this paper it is showed that...
Zero-sumfree sequences in cyclic groups and some arithmetical application
We show that in a cyclic group with elements every zero-sumfree sequence with length contains some element of order with high multiplicity.
Автоморфизмы унипотентных подгрупп групп Шевалле
Два замечания об изоморфизмах коммутативных полугрупп
Исправление к статье "Полупростота алгебры неразложимых представлений конечной коммутативной полугруппы"
Коммутативные полугруппы, решетка подполугрупп которых удовлетворяет нетривиальному тождеству
О двойственности комплексных характеров и полухарактеров коммутативных полугрупп
О матричных представлениях конечных коммутативных полугрупп.
О некоторых алгорифмических задачах для конечно-определенных коммутативных полугрупп