Recursive well-founded orderings

Recursive well-founded orderings
复制标题

有根据的递归排序

DOI:
10.1016/0003-4843(78)90001-3
复制
发表时间:
1978
期刊:
Annals of Mathematical Logic
影响因子:
--
通讯作者:
Keh
Keh
中科院分区:
--
文献类型:
--
作者:
Keh

文献摘要

被引文献

相似文献

设W(~)表示序数小于a的自然数的递归良序的G6 del数集。Kreisel、Shoenfield和Wang [3]、Liu [4]和[5]以及Hay、Manaster和Rosenstein [1]的工作已经完全确定了集合W(a)的多1度。本文将W(a)的多1度的结果推广到所有递归序数a上。作为工具,我们首先研究了W(a)的多1度,其中W(a)是秩小于0的自然数的递归良基偏序的G6 del数的集合,~ ot是第一非递归序数。如表1和表2所示,我们得到了WF(a)和W(c~)的多-一度,其中r(w. [3+ n)= w./ 3+ 2n,n<0。
Let W (~) denote the set of G6del numbers of recursive well-orderings of natural numbers of ordinal less than a. The many-one degrees of the sets W (a) for a< o)'have been completely determined by the accumulated work of Kreisel, Shoenfield, and Wang [3], Liu [4] and [5], and Hay, Manaster and Rosenstein [1]. In this paper, we extend tne results on many-one degrees of W (a) to all recursive ordinals a, As a tool, we first investigate the many-one degrees of WF (a) for< o9~ where WF (a) is the set of G6del numbers of reeursive well-founded partial orderings of natural numbers of rank less than o: and~ ot is the first non-recursbe ordinal. We obtain the many-one degrees of WF (a) and W (c~) as in Tables 1 and2, where r (w.[3+ n)= w./3+ 2n, n< to.