dc.contributor.author |
Batyrshin I. |
|
dc.date.accessioned |
2018-09-18T20:16:44Z |
|
dc.date.available |
2018-09-18T20:16:44Z |
|
dc.date.issued |
2010 |
|
dc.identifier.issn |
1066-369X |
|
dc.identifier.uri |
https://dspace.kpfu.ru/xmlui/handle/net/138225 |
|
dc.description.abstract |
In this work we prove that for every pair of computably enumerable degrees a<Q b there exists a properly 2-computably enumerable degree d such that a <Q d <Q b, a isolates d from below, and b isolates d from above. Two corollaries follow from this result. First, there exists a 2-computably enumerable degree which is Q-incomparable with any nontrivial (different from 0 and 0′) computably enumerable degree. Second, every nontrivial computably enumerable degree isolates some 2-computably enumerable degree from below and some 2-computably enumerable degree from above. © 2010 Allerton Press, Inc. |
|
dc.relation.ispartofseries |
Russian Mathematics |
|
dc.subject |
2-computably enumerable sets |
|
dc.subject |
computably enumerable sets |
|
dc.subject |
isolated degrees |
|
dc.subject |
quasi-reducibility |
|
dc.title |
Isolated 2-computably enumerable Q-degrees |
|
dc.type |
Article |
|
dc.relation.ispartofseries-issue |
4 |
|
dc.relation.ispartofseries-volume |
54 |
|
dc.collection |
Публикации сотрудников КФУ |
|
dc.relation.startpage |
1 |
|
dc.source.id |
SCOPUS1066369X-2010-54-4-SID78649623512 |
|