dc.contributor.author |
Fang C. |
|
dc.contributor.author |
Wu G. |
|
dc.contributor.author |
Yamaleev M. |
|
dc.date.accessioned |
2018-09-18T20:10:39Z |
|
dc.date.available |
2018-09-18T20:10:39Z |
|
dc.date.issued |
2013 |
|
dc.identifier.issn |
0933-5846 |
|
dc.identifier.uri |
https://dspace.kpfu.ru/xmlui/handle/net/137290 |
|
dc.description.abstract |
Given a d.c.e. degree d, consider the d.c.e. sets in d and the corresponding degrees of their Lachlan sets. Ishmukhametov provided a systematic investigation of such degrees, and proved that for a given d.c.e. degree d > 0, the class of its c.e. predecessors in which d is c.e., denoted as R[d], can consist of either just one element, or an interval of c.e. degrees. After this, Ishmukhametov asked whether there exists a d.c.e. degree d for which the class R[d] has no minimal element. We give a positive answer to this question. © 2013 Springer-Verlag Berlin Heidelberg. |
|
dc.relation.ispartofseries |
Archive for Mathematical Logic |
|
dc.subject |
d.c.e. sets |
|
dc.subject |
Lachlan sets |
|
dc.subject |
Turing degrees |
|
dc.title |
On a problem of Ishmukhametov |
|
dc.type |
Article |
|
dc.relation.ispartofseries-issue |
7-8 |
|
dc.relation.ispartofseries-volume |
52 |
|
dc.collection |
Публикации сотрудников КФУ |
|
dc.relation.startpage |
733 |
|
dc.source.id |
SCOPUS09335846-2013-52-78-SID84885605096 |
|