Abstract
Let Tn be the full symmetric semigroup on Xn = {1,2,... ,n} and let OCTn and ORCTn be its subsemigroups of order-preserving and order-preserving or order-reversing full contraction mappings of Xn, respectively. In this paper we investigate the cardinalities of some equivalences on OCT n and ORCTn which lead naturally to obtaining the orders of these subsemigroups.
| Original language | British English |
|---|---|
| Pages (from-to) | 37-49 |
| Number of pages | 13 |
| Journal | Journal of Combinatorial Mathematics and Combinatorial Computing |
| Volume | 106 |
| State | Published - Aug 2018 |