23 search results - page 3 / 5 » An Infinite Antichain of Permutations |
100
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SIAMDM
2010
14 years 10 months ago
2010
K¨orner and Malvenuto asked whether one can find n n/2 linear orderings (i.e., permutations) of the first n natural numbers such that any pair of them places two consecutive int...
86
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AML
2010
14 years 11 months ago
2010
Let J (M2 ) denote the -ideal associated with two-dimensional Miller forcing. We show that it is relatively consistent with ZFC that the additivity of J (M2 ) is bigger than the c...
JSC
2008
14 years 11 months ago
2008
Motivated by the famous 3n + 1 conjecture, we call a mapping from Z to Z residue-class-wise affine if there is a positive integer m such that it is affine on residue classes (mod m...
EJC
2007
14 years 11 months ago
2007
109
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JSYML
2008
14 years 11 months ago
2008
We investigate the structure of the Medvedev lattice as a partial order. We prove that every interval in the lattice is either finite, in which case it is isomorphic to a finite B...