The commutative cohomology of finite semigroups
نویسندگان
چکیده
منابع مشابه
Commutative cancellative semigroups of finite rank
The rank of a commutative cancellative semigroup S is the cardinality of a maximal independent subset of S. Commutative cancellative semigroups of finite rank are subarchimedean and thus admit a Tamura-like representation. We characterize these semigroups in several ways and provide structure theorems in terms of a construction akin to the one devised by T. Tamura for N-semigroups.
متن کاملIsomorphisms and strong finite projec- tive classes of commutative semigroups
In “Sverdlovsk notebook” (Sverdlovsk, 1969), I proposed a question: Are any too first-order equivalent finitely generated commutative semigroups isomorphic? In 1970, B.I.Zilber answered the question negatively. A question arises: In what language, any equivalent over the language finitely generated commutative semigroups are isomorphic? In the note, we propose such a language. Moreover, we prov...
متن کاملVarieties of Commutative Semigroups
In this paper, we describe all equational theories of commutative semigroups in terms of certain well-quasi-orderings on the set of finite sequences of nonnegative integers. This description yields many old and new results on varieties of commutative semigroups. In particular, we obtain also a description of the lattice of varieties of commutative semigroups, and we give an explicit uniform sol...
متن کاملTotally Ordered Commutative Semigroups
Let 5( + , < ) be a system consisting of a set S endowed with an associative binary operation + and a total ( = linear = simple) order relation < . The composition + and the relation < may be connected by either or both of the following conditions. MC (Monotone Condition). If a and b are elements of 5 such that ax+y ...
متن کاملZero-divisor Graphs of Finite Direct Products of Finite Non-commutative Rings and Semigroups
We determine the number of edges of the zero-divisor graph of the direct product of finitely many finite non-commutative rings or semigoups.
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Journal of Pure and Applied Algebra
سال: 1995
ISSN: 0022-4049
DOI: 10.1016/0022-4049(94)00064-p