Sums of at least $9$ ordinals.
نویسندگان
چکیده
منابع مشابه
Computable shuffle sums of ordinals
The main result is that for sets S ⊆ ω + 1, the following are equivalent: (1) The shuffle sum σ(S) is computable. (2) The set S is a liminf set, i.e. there is a total computable function g(x, t) such that f(x) = lim inft g(x, t) enumerates S. (3) The set S is a limitwise monotonic set relative to 0′, i.e. there is a total 0′-computable function g̃(x, t) satisfying g̃(x, t) ≤ g̃(x, t + 1) such that...
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ژورنال
عنوان ژورنال: Notre Dame Journal of Formal Logic
سال: 1973
ISSN: 0029-4527
DOI: 10.1305/ndjfl/1093890902