Now showing items 1-8 of 8

    • IconLos q-polinomios hipergeométricos  [Chapter of Book]

      Álvarez Nodarse, Renato (Universidad de La Rioja, 2001)
      It is well known that the q-polynomials of hypergeometric type are the polynomial solutions of a certain second order difference equation in a non-uniform lattice. In this short paper we present a modification of the proof ...
    • IconEl principio de Calderón-Zygmund  [Chapter of Book]

      Pérez Moreno, Carlos; Trujillo González, Rodrigo Francisco (Universidad de La Rioja, 2001)
      In this note we show some estimates for multilinear commutators with vector symbol b = (b1,...,bm) defined by the expression Tbf(x) = Z Rn2 4Ym j=1 (bj (x) − bj (y)) 3 5 K(x, y)f(y) dy, where K is the kernel of any ...
    • IconIntroduction to hyperconvex spaces  [Chapter of Book]

      Espínola García, Rafael; Khamsi, Mohamed Amine (Springer, 2001)
      The notion of hyperconvexity is due to Aronszajn and Panitchpakdi (1956) who proved that a hyperconvex space is a nonexpansive absolute retract, i.e. it is a nonexpansive retract of any metric space in which it is isometrically ...
    • IconOn the sign of the real part of the Riemann zeta-function  [Chapter of Book]

      Arias de Reyna Martínez, Juan; Brent, Richard P.; Van de Lune, Jan (Springer, 2013)
      We consider the distribution of argζ(σ +it) on fixed lines σ > 1/2, and in particular the density d(σ) = lim T→+∞ 1/2T |{t ∈ [−T,+T] : |argζ(σ +it)| > π/2}|, and the closely related density d−(σ) = lim T→+∞ 1/2T |{t ∈ ...
    • IconImproving bounds for singular operators via sharp reverse Hölder inequality for A∞  [Chapter of Book]

      Ortiz Caraballo, Carmen María; Pérez Moreno, Carlos; Rela, Ezequiel (Springer, 2013)
      In this expository article we collect and discuss some recent results on different consequences of a Sharp Reverse Hölder Inequality for A∞ weights. For two given operators T and S, we study Lp(w) bounds of CoifmanFefferman ...
    • IconExistence and approximation of fixed points of right Bregman nonexpansive operators  [Chapter of Book]

      Martín Márquez, Victoria; Reich, Simeon; Sabach, Shoham (Springer, 2013-07-29)
      We study the existence and approximation of fixed points of right Bregman nonexpansive operators in reflexive Banach space. We present, in particular, necessary and sufficient conditions for the existence of fixed points ...
    • IconRefined size estimates for Furstenberg sets via Hausdorff measures: a survey of some recent results  [Chapter of Book]

      Rela, Ezequiel (Springer, 2014)
      In this survey we collect and discuss some recent results on the so called “Furstenberg set problem”, which in its classical form concerns the estimates of the Hausdorff dimension (dimH) of the sets in the Fα-class: for ...
    • IconA note on the off-diagonal Muckenhoupt-Wheeden conjecture  [Chapter of Book]

      Cruz Uribe, David; Martell Berrocal, José María; Pérez Moreno, Carlos (World Scientific, 2016)
      We obtain the off-diagonal Muckenhoupt-Wheeden conjec-ture for Calder´on-Zygmund operators. Namely, given 1 < p < q < ∞ and a pair of weights (u, v), if the Hardy-Littlewood maximal functionsatisfies the following two weight ...