Combinatorial results for order-preserving partial injective contraction mappings

Bayo Musa Ahmed, Nadia Aldhamri, Fatma Al-Kharousi +2

Let ${\mathcal{I}}_n$ be the symmetric inverse semigroup on $X_n=\{1,2,\dots ,n\}$. Let ${\mathcal{O}\mathcal{C}\mathcal{I}}_n$ be the subsemigroup of ${\mathcal{I}}_n$ consisting of all order-preser…