The extremal functions f0(z) realizing the maxima of some functionals (e.g. max |a3|, and max arg f′(z)) within the so-called universal linearly invariant family Uα (in the sense of Pommerenke [10]) have such a form that f′0(z) looks similar to generating function for Meixner-Pollaczek (MP) polynomials [2], [8]. This fact gives motivation for the definition and study of the generalized Meixner-Pollaczek (GMP) polynomials Pλn (x; θ,ψ) of a real variable x as coefficients of [###] where the parameters λ, θ, ψ satisfy the conditions: λ > 0, θ ∈ (0, π), ψ ∈ R. In the case ψ =− θ we have the well-known (MP) polynomials. The cases ψ = π − θ and ψ = π + θ leads to new sets of polynomials which we call quasi-Meixner-Pollaczek polynomials and strongly symmetric Meixner-Pollaczek polynomials. If x = 0, then we have an obvious generalization of the Gegenbauer polynomials. The properties of (GMP) polynomials as well as of some families of holomorphic functions |z| < 1 defined by the Stieltjes-integral formula, where the function zGλ(x; θ,ψ; z) is a kernel, will be discussed.
@article{bwmeta1.element.doi-10_2478_v10062-012-0021-1, author = {Iwona Naraniecka and Jan Szynal and Anna Tatarczak}, title = {Linearly-invariant families and generalized Meixner--Pollaczek polynomials}, journal = {Annales UMCS, Mathematica}, volume = {67}, year = {2013}, pages = {45-56}, zbl = {06277079}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.doi-10_2478_v10062-012-0021-1} }
Iwona Naraniecka; Jan Szynal; Anna Tatarczak. Linearly-invariant families and generalized Meixner–Pollaczek polynomials. Annales UMCS, Mathematica, Tome 67 (2013) pp. 45-56. http://gdmltest.u-ga.fr/item/bwmeta1.element.doi-10_2478_v10062-012-0021-1/
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