Now showing items 201-220 of 759

    • New method to solve certain differential equations 

      Rajchel, Kazimierz; Szczęsny, Jerzy (2016)
      A new method to solve stationary one-dimensional Schroedinger equation is investigated. Solutions are described by means of representation of circles with multiple winding number. The results are demonstrated using the ...
    • Properties of two variables Toeplitz type operators 

      Król-Klimkowska, Elżbieta; Ptak, Marek (2016)
      The investigation of properties of generalized Toeplitz operators with respect to the pairs of doubly commuting contractions (the abstract analogue of classical two variable Toeplitz operators) is proceeded. We ...
    • Affine analogues of the Sasaki-Shchepetilov connection 

      Robaszewska, Maria (2016)
      For two-dimensional manifold $M$ with locally symmetric connection $∇$ and with $∇-parallel$ volume element vol one can construct a flat connection on the vector bundle $TM ⊕ E$, where $E$ is a trivial bundle. The ...
    • On some flat connection associated with locally symmetric surface 

      Robaszewska, Maria (2014)
      For every two-dimensional manifold $M$ with locally symmetric linear connection $∇$, endowed also with $∇-parallel$ volume element, we construct a flat connection on some principal fibre bundle $P(M,G)$. Associated with ...
    • Simple proofs of some generalizations of the Wilson’s theorem 

      Górowski, Jan; Łomnicki, Adam (2014)
      In this paper a remarkable simple proof of the Gauss’s generalization of the Wilson’s theorem is given. The proof is based on properties of a subgroup generated by element of order 2 of a finite abelian group. Some conditions ...
    • A note on some iterative roots 

      Solarz, Paweł (2009)
      In this paper some orientation-preserving iterative roots of an orientation-preserving homeomorphism $F:S^1 ⟶ S^1$ which possess periodic points of order $n$ are considered. Namely, iterative roots with periodic points ...
    • On a multivalued second order differential problem with Jensen multifunction 

      Piszczek, Magdalena (2009)
      The aim of this paper is to present a generalization of the results published in [5] and [8] for continuous Jensen multifunctions. In particular, we study a second order differential problem for multifunctions with the ...
    • On conjugacy of multivalent functions on the circle 

      Zdun, Marek Cezary (2000)
      We prove that every two expanding selfmappings of the circle which take each value in exactly n points are conjugate. The problem of the uniqueness of continuous conjugating functions is considered. Moreover, some ...
    • Global version of a Sternberg linearization theorem 

      Zajtz, Andrzej (2000)
      Let X{x) = DX(0)x + Z(x) be a smooth vector field in R[n], with X (0) = 0, such that 0 is a contracting singular point of the linear part. We aim to extend the local Sternberg theorem on the linearization of X near the ...
    • On a Gauss-Weierstrass generalized integral 

      Wachnicki, Eugeniusz (2000)
    • Entire solutions of a functional equation 

      Smajdor, Andrzej; Smajdor, Wilhelmina (2000)
      The aim of the present note is to show that all entire solutions f : C → C, of order less than 4, of the equation |f(s + it)f(s - it)| = |f(s)[2] - f(it)[2]|, s,t ϵ R are given by f(z) — az and f(z) = a sin bz, where a, ...
    • The rotation number of the composition of homeomorphisms 

      Ciepliński, Krzysztof (2000)
      In this paper it is shown that if F and G are commuting orientation-preserving homeomorphisms of the unit circle, then α(F ◦ G) = α(F) + α(G) (mod 1), where α(F) denotes the rotation number of F.
    • A functional inequality related to Böttcher’s equation 

      Brydak, Dobiesław; Choczewski, Bogdan (2000)
      There is proved a theorem on the form of continuous solutions of the iterative functional inequality (1) in the case where the function f in (1) possesses an asymptotic property at the origin. The formula we present ...
    • An alternative Cauchy equation almost everywhere 

      Batko, Bogdan (2000)
      Let (S, +) be a commutative semigroup and let ζ be a proper left translation invariant σ-ideal in S. Suppose that f : S → R satisfies |f(x + y)| = |f(x) + f(y)| Ω(ζ)-almost everywhere in S x S. We prove that there exists, ...
    • Sur une équation intégro-fonctionnelle 

      Wachnicki, Eugeniusz (1999)
    • Concave itération semigroups of Jensen set-valued functions 

      Smajdor, Andrzej (1999)
      Let S be a closed convex cone such that int S ≠ 0 in a real separable Banach space. A necessary and sufficient condition is given under which a family {F[t] : t ≥ 0} of set-valued functions F[t] : S -> cc(S) is a concave ...
    • L’équation de translation et l’équation de Sincov généralisée 

      Moszner, Zenon (1999)
      On donne une liaison entre l’équation de translation (1) et l’équation de Sincov généralisée (2), aussi dans le cas du type de Pexider ((20) et (23)). On formule aussi quelques problèmes ouverts.
    • The first International Conference on Functional Equations in Poland : Zakopane 1967 

      Choczewski, Bogdan (1999)
      The meeting in 1967 was organized by Professors Stanisław Gołąb and Marek Kuczma. It was held in Tatra mountains and was the first international conference on functional equations organized in Poland. For most of Polish ...
    • Superadditive solutions of functional equation 

      Smajdor, Andrzej (1998)
      Let {A[s] : s ≥ 0} be a given iteration semigroup of additive set-valued functions. In this paper we study superadditive set-valued solutions Ф of the functional equation Ф(t + s) = A[s] [Ф(t)] + Ф(s) for t, s ≥ 0.