1 citations · 5 across the 10 of their papers we have counts for
Showing 2000Show all
3 papers · 1 filter
math.FA2000
A discrete form of the Beckman-Quarles theorem for two-dimensional strictly convex normed spaces
Apoloniusz Tyszka
Let X be a real normed vector space and dim X \ge 2. Let d>0 be a fixed real number. We prove that if x,y \in X and ||x-y||/d is a rational number then there exists a finite set {x…
math.LO2000
On binary relations without non-identical endomorphisms
Apoloniusz Tyszka
On every set A there is a rigid binary relation, i.e. such a relation R that there is no homomorphism (A,R)->(A,R) except the identity (Vopenka et al. [1965]). We state two conject…
math.LO2000
A combinatorial characterization of second category subsets of X^ω
Apoloniusz Tyszka
Let a finite non-empty X is equipped with discrete topology. We prove that S \subseteq X^ωis of second category if and only if for each f:ω-> \bigcup_{n \in ω} X^n there exists a s…