Abstract
We calculate the rank and idempotent rank of the semigroup E(X,P) generated by the idempotents of the semigroup T(X,P), which consists of all transformations of the finite set X preserving a non-uniform partition P. We also classify and enumerate the idempotent generating sets of this minimal possible size. This extends results of the first two authors in the uniform case.
Original language | English |
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Pages (from-to) | 73-91 |
Journal | Bulletin of the Australian Mathematical Society |
Volume | 93 |
Issue number | 1 |
Early online date | 10 Aug 2015 |
DOIs | |
Publication status | Published - Feb 2016 |
Keywords
- Transformation semigroups
- Idempotents
- Generators
- Rank
- Idempotent rank