In this paper we describe the covering relation in the lattice of the equational theories of commutative semigroups. We use the description and the methods worked out in an earlier paper by the second author [1994, Trans. Amer. Math. Soc. 342, 275-306].
Perfect Bases for Equational Theories
✍ Scribed by Jaroslav Ježek; George F. McNulty
- Publisher
- Elsevier Science
- Year
- 1995
- Tongue
- English
- Weight
- 624 KB
- Volume
- 19
- Category
- Article
- ISSN
- 0747-7171
No coin nor oath required. For personal study only.
✦ Synopsis
Perfect bases for equational theories are closely related to confluent and finitely terminating term rewrite systems. The two classes have a large overlap, but neither contains the other. The class of perfect bases is recursive. We also investigate a common generalization of both concepts; we call these more general bases normal, and touch the question of their uniqueness. We also give numerous examples.
📜 SIMILAR VOLUMES
In classical rook theory there is a fundamental relationship between the rook numbers and the hit numbers relative to any board. In that theory the k-th hit number of a board B can be interpreted as the number of permutations whose intersection with B is of size k. In the case of Ferrers boards ther