Embedding finite lattices into the ideals of computably enumerable turing degrees
Keyword(s):
Abstract.We show that the lattice L20 is not embeddable into the lattice of ideals of computably enumerable Turing degrees (ℐ), We define a structure called a pseudolattice that generalizes the notion of a lattice, and show that there is a Π2 necessary and sufficient condition for embedding a finite pseudolattice into ℐ.
2000 ◽
Vol 101
(2-3)
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pp. 275-297
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2001 ◽
Vol 112
(1)
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pp. 1-26
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1998 ◽
Vol 94
(1-3)
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pp. 143-180
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2017 ◽
Vol E100.A
(12)
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pp. 2764-2775
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