Abstract
We analyze results on well-partial-orderings from the viewpoint of computability theory, and we answer a question posed by Diana Schmidt. We obtain the following results. De Jongh and Parikh showed that every well-partial-order has a linearization of maximal order type. We show that such a linearization can be found computably. We also show that the process of finding such a linearization is not computably uniform, not even hyperarithmetically.
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Montalbán, A. Computable Linearizations of Well-partial-orderings. Order 24, 39–48 (2007). https://doi.org/10.1007/s11083-007-9058-0
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DOI: https://doi.org/10.1007/s11083-007-9058-0