论文信息 - Upward closure and cohesive degrees - 字舞流文

Upward closure and cohesive degrees

It is shown that the degrees of unsolvability of sets having almost any sort of immunity or cohesiveness property studied in recursion theory are closed upwards. From this it follows that every degreea witha′≧0″ contains a cohesive set.

Carl G. Jockusch

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