Submonoids of groups, and group-representability of restricted relation algebras
- Author(s): Bergman, GM
- et al.
Published Web Locationhttps://math.berkeley.edu/~gbergman/papers/u_d_u_d.pdf
© 2018, Springer International Publishing AG, part of Springer Nature. Marek Kuczma asked in 1980 whether for every positive integer n, there exists a subsemigroup M of a group G, such that G is equal to the n-fold product MM-1MM-1…M(-1)n-1, but not to any proper initial subproduct of this product. We answer his question affirmatively, and prove a more general result on representing a certain sort of relation algebra by a family of subsets of a group. We also sketch several variants of the latter result.