Let POn be the semigroup of all order-preserving partial transformations of a finite chain. It is shown that POn =cn satisfies the recurrence (2n-1)(n+1)cn+1=4 (3n2-1 cn-(2n+1) (n-1)cn-1 with initial conditions c0=1, c1=2. It is also shown that E(POn) =en satisfies the recurrence en+1=5(en-en-1)+1 with initial conditions e0=1, e1=2. Moreover, the cardinalities of the Green's relations L, R and J have been computed.
ASJC Scopus subject areas
- Algebra and Number Theory