Exact unprovability results for compound well-quasi-ordered combinatorial classes
نویسنده
چکیده
In this paper we prove general exact unprovability results that show how a threshold between provability and unprovability of a finite well-quasi-orderedness assertion of a combinatorial class is transformed by the sequence-construction, multisetconstruction, cycle-construction and labeled-tree-construction. Provability proofs use asymptotic pigeonhole principle, unprovability proofs use Weiermann-style compression techniques and results from analytic combinatorics.
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ورودعنوان ژورنال:
- Ann. Pure Appl. Logic
دوره 157 شماره
صفحات -
تاریخ انتشار 2009