On the Cofinality of Infinite Partially Ordered Sets: Factoring a Poset into Lean Essential Subsets
نویسندگان
چکیده
We study which infinite posets have simple cofinal subsets such as chains, or decompose canonically into such subsets. The posets of countable cofinality admitting such a decomposition are characterized by a forbidden substructure; the corresponding problem for uncountable cofinality remains open.
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ورودعنوان ژورنال:
- Order
دوره 20 شماره
صفحات -
تاریخ انتشار 2003