Turkish Journal of Mathematics, cilt.50, sa.2, ss.228-239, 2026 (SCI-Expanded, Scopus, TRDizin)
Let OPCTₙ (OCTₙ) denote the semigroup consisting of all orientation-preserving (order-preserving) full contraction mappings on the finite chain Xₙ={1<;n}, and let OPDCTₙ (ODCTₙ) denote the subsemigroup of OPCTₙ (OCTₙ) consisting of all order-decreasing transformations. The purpose of this paper is to determine the cardinalities of OPCTₙ, OPCTₙ, N(ODCTₙ), and N(OPDCTₙ), and to identify generating sets of minimal size, thereby determining their ranks. Moreover, the number of idempotents of OPDCTₙ is determined.