On the Chain Blockers of a Poset
نویسنده
چکیده
Let P = Ca × Cb be a poset where Ci is the chain 1 < · · · < i. A chain blocker of P is an inlcusionwise minimal subset B ⊆ P with the property that every maximal chain in P contains at least one element of B. In [1] the chain blockers of P are being expressed in term of the Catalan numbers and k fold convolution of the Catalan numbers. In this paper we give a complete description of the chain blockers of Ca × Cb, where a ≤ 4 and b ≥ 1. In the end algebraic consequences of the chain blockers are also provided.
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تاریخ انتشار 2016