Results 11 to 20 of about 34 (33)
Journal of Applied Mathematics, Volume 2004, Issue 5, Page 359-369, 2004., 2004 Using a general and simple algebraic approach, some results on Krall‐type orthogonal polynomials and some of their extensions are obtained.
R. Álvarez-Nodarse +2 more
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The second‐order self‐associated orthogonal sequences
Journal of Applied Mathematics, Volume 2004, Issue 2, Page 137-167, 2004., 2004 The aim of this work is to describe the orthogonal polynomials sequences which are identical to their second associated sequence. The resulting polynomials are semiclassical of class s ≤ 3. The characteristic elements of the structure relation and of the second‐order differential equation are given explicitly.
P. Maroni, M. Ihsen Tounsi
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Strict positive definiteness on spheres via disk polynomials
International Journal of Mathematics and Mathematical Sciences, Volume 31, Issue 12, Page 715-724, 2002., 2002 We characterize complex strictly positive definite functions on spheres in two cases, the unit sphere of ℂq, q ≥ 3, and the unit sphere of the complex ℓ2. The results depend upon the Fourier‐like expansion of the functions in terms of disk polynomials and, among other things, they enlarge the classes of strictly positive definite functions on real ...
V. A. Menegatto, A. P. Peron
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On the existence of complex Hadamard submatrices of the Fourier matrices
Demonstratio Mathematica, 2019 We use a theorem of Lam and Leung to prove that a submatrix of a Fourier matrix cannot be Hadamard for particular cases when the dimension of the submatrix does not divide the dimension of the Fourier matrix.
Bond Bailey Madison +2 more
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International Journal of Mathematics and Mathematical Sciences, Volume 26, Issue 8, Page 449-455, 2001., 2001 We study the asymptotic behavior of orthogonal polynomials. The measure is concentrated on a complex rectifiable arc and has an infinity of masses in the region exterior to the arc.
R. Khaldi, R. Benzine
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International Journal of Mathematics and Mathematical Sciences, Volume 24, Issue 10, Page 673-689, 2000., 2000 We give explicitly the recurrence coefficients of a nonsymmetric semi‐classical sequence of polynomials of class s = 1. This sequence generalizes the Jacobi polynomial sequence, that is, we give a new orthogonal sequence {Pˆn(α,α+1)(x,μ)}, where μ is an arbitrary parameter with ℜ(1 − μ) > 0 in such a way that for μ = 0 one has the well‐known Jacobi ...
Mohamed Jalel Atia
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On 2‐orthogonal polynomials of Laguerre type
International Journal of Mathematics and Mathematical Sciences, Volume 22, Issue 1, Page 29-48, 1999., 1999 Let be a sequence of 2‐orthogonal monic polynomials relative to linear functionals ω0 and ω1 (see Definition 1.1). Now, let be the sequence of polynomials defined by . When is, also, 2‐orthogonal, is called “classical” (in the sense of having the Hahn property). In this case, both and satisfy a third‐order recurrence relation (see below).
Khalfa Douak
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Fractal multiwavelets related to the cantor dyadic group
International Journal of Mathematics and Mathematical Sciences, Volume 21, Issue 2, Page 307-314, 1998., 1997 Orthogonal wavelets on the Cantor dyadic group are identified with multiwavelets on the real line consisting of piecewise fractal functions. A tree algorithm for analysis using these wavelets is described. Multiwavelet systems with algorithms of similar structure include certain orthogonal compactly supported multiwavelets in the linear double‐knot ...
W. Christopher Lang
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Complex and distributional weights for sieved ultraspherical polynomials
International Journal of Mathematics and Mathematical Sciences, Volume 19, Issue 2, Page 229-242, 1996., 1993 Contour integral and distributional orthogonality of sieved ultraspherical polynomials are established for values of the parameters outside the natural range of orthogonality by positive measures on the real line. A general representation theorem for moment functionals is included.
Jairo A. Charris, Felix H. Soriano
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Numerical treatments of nonlinear Burgers–Fisher equation via a combined approximation technique
Kuwait Journal of ScienceA combined spectral matrix collocation strategy is presented to solve the time-dependent nonlinear Burgers–Fisher equation pertaining to various important physical mechanisms such as advection, diffusion, and logistic reaction.
Mohammad Izadi, Hari Mohan Srivastava
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