Издательство: | Книга по требованию |
Дата выхода: | июль 2011 |
ISBN: | 978-6-1331-0586-7 |
Объём: | 84 страниц |
Масса: | 147 г |
Размеры(В x Ш x Т), см: | 23 x 16 x 1 |
Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. In algebra, a presentation of a monoid (or semigroup) is a description of a monoid (or semigroup) in terms of a set of generators and a set of relations on the free monoid * (or free semigroup +) generated by . The monoid is then presented as the quotient of the free monoid by these relations. This is an analogue of a group presentation in group theory. As a mathematical structure, a monoid presentation is identical to a string rewriting system (also known as semi-Thue system). Every monoid may be presented by a semi-Thue system (possibly over an infinite alphabet). The relations are given as a (finite) binary relation R on *. To form the quotient monoid, these relations are extended to monoid congruences as follows. First one takes the symmetric closure R R–1 of R. This is then extended to a symmetric relation E * x * by defining x ~E y if and only if x = sut and y = svt for some strings u, v, s, t * with (u,v) R R–1. Finally, one takes the reflexive and transitive closure of E, which is then a monoid congruence.
Данное издание не является оригинальным. Книга печатается по технологии принт-он-деманд после получения заказа.