Abstract
In this paper, a new lowering operator D u with a linear functional u as a parameter is introduced in the linear space ℙ of all polynomials in one variable with complex coefficients. It is given by
Acknowledgements
The first author (F.M.) was supported by Dirección General de Investigación, Ministerio de Ciencia e Innovación of Spain, under grant MTM 2009-12740-C03-01. The work of the second author (R.S.) was supported by Faculté des Sciences de Gabès and Faculté des Sciences de Sfax, Tunisia.