共查询到20条相似文献,搜索用时 578 毫秒
1.
When do linear combinations of orthogonal polynomials yield new sequences of orthogonal polynomials?
Manuel Alfaro Francisco Marcellán M. Luisa Rezola 《Journal of Computational and Applied Mathematics》2010,233(6):1446-1452
Given {Pn}n≥0 a sequence of monic orthogonal polynomials, we analyze their linear combinations with constant coefficients and fixed length, i.e.,
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Z. Ditzian 《Journal of Mathematical Analysis and Applications》2011,384(2):303-306
For expansion by Jacobi polynomials we relate smoothness given by appropriate K-functionals in Lp, 1?p?2, to estimates on the coefficients in the ?q form. As a corollary for 1<p?2, and an the coefficients of the Legendre expansion of f∈Lp[−1,1], we obtain the estimate
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We define a functional analytic transform involving the Chebyshev polynomials Tn(x), with an inversion formula in which the Möbius function μ(n) appears. If s∈C with Re(s)>1, then given a bounded function from [−1,1] into C, or from C into itself, the following inversion formula holds:
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Pieter C. Allaart 《Journal of Mathematical Analysis and Applications》2011,381(2):689-694
Let ?(x)=2inf{|x−n|:n∈Z}, and define for α>0 the function
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J. Petronilho 《Journal of Mathematical Analysis and Applications》2006,315(2):379-393
An inverse problem is solved, by stating that the regular linear functionals u and v associated to linearly related sequences of monic orthogonal polynomials n(Pn) and n(Qn), respectively, in the sense
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Vladimir Petrov Kostov 《Bulletin des Sciences Mathématiques》2007,131(5):477
A real polynomial P of degree n in one real variable is hyperbolic if its roots are all real. A real-valued function P is called a hyperbolic polynomial-like function (HPLF) of degree n if it has n real zeros and P(n) vanishes nowhere. Denote by the roots of P(i), k=1,…,n−i, i=0,…,n−1. Then in the absence of any equality of the form one has ∀i<j, (the Rolle theorem). For n?4 (resp. for n?5) not all arrangements without equalities (∗) of n(n+1)/2 real numbers and compatible with (∗∗) (we call them admissible) are realizable by the roots of hyperbolic polynomials (resp. of HPLFs) of degree n and of their derivatives. For n=5 we show that from 286 admissible arrangements, exactly 236 are realizable by HPLFs; from these 236 arrangements, 116 are realizable by hyperbolic polynomials and 24 by perturbations of such. 相似文献
8.
Thomas Stoll 《Journal of Number Theory》2008,128(5):1157-1181
We characterize decomposition over C of polynomials defined by the generalized Dickson-type recursive relation (n?1)
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Let be a sequence of i.i.d. random variables taking values in a real separable Hilbert space (H,‖⋅‖) with covariance operator Σ, and set Sn=X1+?+Xn, n?1. Let . We prove that, for any 1<r<3/2 and a>−d/2,
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J. Mc Laughlin 《Journal of Number Theory》2007,127(2):184-219
Let f(x)∈Z[x]. Set f0(x)=x and, for n?1, define fn(x)=f(fn−1(x)). We describe several infinite families of polynomials for which the infinite product
12.
Th. Stoll 《Indagationes Mathematicae》2003,14(2):263-274
Let A, B, C denote rational numbers with AB ≠ 0 and m > n ≥ 3 arbitrary rational integers. We study the Diophantine equation APm(x) + Bpn(y) = C, in x, y ? , where {Pk(x)}I is one of the three classical continuous orthogonal polynomial families, i.e. Laguerre polynomials, Jacobi polynomials (including Gegenbauer, Legendre or Chebyshev polynomials) and Hermite polynomials. We prove that with exception of the Chebyshev polynomials for all such polynomial families there are at most finitely many solutions (x, y) ? 2 provided n > 4. The tools are besides the criterion [3], a theorem of Szeg— [14] on monotonicity of stationary points of polynomials which satisfy a second order Sturm-Liouville differential equation,
13.
Enrique Arrondo 《Journal of Pure and Applied Algebra》2011,215(3):201-220
The purpose of this paper is to relate the variety parameterizing completely decomposable homogeneous polynomials of degree d in n+1 variables on an algebraically closed field, called , with the Grassmannian of (n−1)-dimensional projective subspaces of Pn+d−1. We compute the dimension of some secant varieties to . Moreover by using an invariant embedding of the Veronese variety into the Plücker space, we are able to compute the intersection of G(n−1,n+d−1) with , some of its secant varieties, the tangential variety and the second osculating space to the Veronese variety. 相似文献
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We study isomorphic properties of two generalizations of intersection bodies - the class of k-intersection bodies in Rn and the class of generalized k-intersection bodies in Rn. In particular, we show that all convex bodies can be in a certain sense approximated by intersection bodies, namely, if K is any symmetric convex body in Rn and 1≤k≤n−1 then the outer volume ratio distance from K to the class can be estimated by
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Jang Soo Kim 《Discrete Mathematics》2010,310(8):1398-1400
We prove bijectively that the total number of cycles of all even permutations of [n]={1,2,…,n} and the total number of cycles of all odd permutations of [n] differ by (−1)n(n−2)!, which was stated as an open problem by Miklós Bóna. We also prove bijectively the following more general identity:
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Dimitar K. Dimitrov 《Journal of Mathematical Analysis and Applications》2004,299(1):127-132
We prove that the zeros of the polynomials Pm(a) of degree m, defined by Boros and Moll via
20.
Thierry Aubin 《Journal of Functional Analysis》2007,242(1):78-85
On a compact Riemannian manifold (Vn,g)(n>2), when the conformal Laplacian L is invertible, we show, under necessary hypotheses, that if the Green function GL of L is of the form (here r=d(P,Q)) GL(P,Q)=1/(n−2)ωn−1rn−2+H(P,Q) with H(P,Q) bounded on V, then