A choice set for a computable linear ordering is a set which contains one element from each maximal block of the ordering. We obtain a partial characterization of the computable linear order-types for which each computable model has a computable choice set, and a full characterization in the relativized case; Every model of the linear order-type α of degree ≤ d iff α can written as a finite sum of order-types, each of which either has finitely many blocks, or has order-type n·n for some integer n.
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