Smooth measures, the Malliavin calculus and approximations in infinitedimensional spaces
Given a polyhedral convex function g: ℝⁿ → ℝ ∪ +∞, it is always possible to construct a family which converges pointwise to g and such that each gₜ: ℝⁿ → ℝ is convex and infinitely often differentiable. The construction of such a family involves the concept of cumulant transformation and a standard homogenization procedure.
We consider a compact set K ⊂ ℝ in the form of the union of a sequence of segments. By means of nearly Chebyshev polynomials for K, the modulus of continuity of the Green functions is estimated. Markov’s constants of the corresponding set are evaluated.
2000 Mathematics Subject Classification: 94A12, 94A20, 30D20, 41A05.We characterize Paley-Wiener-Schwartz space of entire functions as a union of three-parametric linear normed subspaces determined by the type of the entire functions, their polynomial asymptotic on the real line, and the index p ≥ 1 of a Sobolev type Lp-summability on the real line with an appropriate weight function. An entire function belonging to a sub-space of the decomposition is exactly recovered by a sampling series, locally...
El objeto del trabajo es la determinación de una cota superior del número real ρ definido comoρ = límn→∞ ρn ρn-n = MinPn∈Hn Max0≤x≤1 |Pn(X)|H n clase de polinomios no nulos con coeficientes en Z y grado menor o igual a n.En un artículo anterior (RMHA, 4 serie, t. XXXVIII, nº 6, 1978, pp. 259-270) el autor muestra que dado (λ1,...,λn) sistema completo de números reales algebraicos y algebraicamente conjugados, verificando:0 ≤ 1/λi+s ≤ 1 ∀i, ∃ s ∈ Zy definiendoδ = (∏i=1m |λi+s|)1/mse verifica ρ...
We consider the problem of calculating a closed form expression for the integral of a real-valued function f:ℝⁿ → ℝ on a set S. We specialize to the particular cases when S is a convex polyhedron or an ellipsoid, and the function f is either a generalized polynomial, an exponential of a linear form (including trigonometric polynomials) or an exponential of a quadratic form. Laplace transform techniques allow us to obtain either a closed form expression, or a series representation that can be handled...
This paper we introducing a new sequence of positive q-integral new Modified q-Szász-Mirakyan Operators. We show that it is a weighted approximation process in the polynomial space of continuous functions defined on . Weighted statistical approximation theorem, Korovkin-type theorems for fuzzy continuous functions, an estimate for the rate of convergence and some properties are also obtained for these operators.