Transitive ternary relations and quasiorderings
Two constructions of compatible relations
Über Mengen mit Trennrelationen
Un théorème en Algèbre et en Analyse.
Una classe di soluzioni con zeri dell'equazione funzionale di Aleksandrov.
In this paper we consider the Aleksandrov equation f(L + x) = f(L) + f(x) where L is contained in Rn and f: L --> R and we describe the class of solutions bounded from below, with zeros and assuming on the boundary of the set of zeros only values multiple of a fixed a > 0. This class is the natural generalization of that described by Aleksandrov itself in the one-dimensional case.
Unbouded descending infinite chain in Rudin-Frolík order
Universal cyclic relations
Universality of the μ-predictor
For suitable topological spaces X and Y, given a continuous function f:X → Y and a point x ∈ X, one can determine the value of f(x) from the values of f on a deleted neighborhood of x by taking the limit of f. If f is not required to be continuous, it is impossible to determine f(x) from this information (provided |Y| ≥ 2), but as the author and Alan Taylor showed in 2009, there is nevertheless a means of guessing f(x), called the μ-predictor, that will be correct except on a small set; specifically,...
Varieties having distributive lattices of quasiorders
Verbände von Kernen isotoner Abbildungen
Zu Äquivalenz- und Ordnungsrelationen
Δ₁-Definability of the non-stationary ideal at successor cardinals
Assuming V = L, for every successor cardinal κ we construct a GCH and cardinal preserving forcing poset ℙ ∈ L such that in the ideal of all non-stationary subsets of κ is Δ₁-definable over H(κ⁺).
-ideals in the lattice of semi -ideals
-Hamiltonian and -regular algebraic structures
The concept of a -closed subset was introduced in [1] for an algebraic structure of type and a set of open formulas of the first order language . The set of all -closed subsets of forms a complete lattice whose properties were investigated in [1] and [2]. An algebraic structure is called - hamiltonian, if every non-empty -closed subset of is a class (block) of some congruence on ; is called - regular, if for every two , whenever they have a congruence class in common....
Инварианты квазиклеток итеративных алгебр Поста.
Итерированные операции и R- операция
О единственности линейных продолжений частичных порядков
О некоторых вопросах, связанных с теоретико- множественными операциями
О перестановочности теоретико-множественных операций со счетным индексным множеством
О регулярности элементов релятива