An Infinite Antichain of Permutations
نویسندگان
چکیده
We constructively prove that the partially ordered set of finite permutations ordered by deletion of entries contains an infinite antichain.
منابع مشابه
Subclasses of the Separable Permutations
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A permutation is an arrangement of a finite number of distinct elements of a linear order, for example, e, π, 0, √ 2 and 3412. Two permutations are order isomorphic if the have the same relative ordering. We say a permutation τ contains or involves the permutation β if deleting some of the entries of τ gives a permutation that is order isomorphic to β, and we write β ≤ τ . For example, 534162 (...
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عنوان ژورنال:
- Electr. J. Comb.
دوره 7 شماره
صفحات -
تاریخ انتشار 2000