An algorithmic approach to maximal unions of chains in a partially ordered set
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چکیده
We exhibit a recursive procedure that enables us to construct a maximal union of k chains in a nite partially ordered set P for every positive integer k. As a consequence, we obtain an algorithmic proof of Greene's Duality Theorem on the relations between the cardinalities of maximal unions of chains and antichains in a nite poset. Mathematics Subject Classi cations (2000). 05A17, 06A07, 68Q25, 65Y25
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تاریخ انتشار 2005