On m-symmetric d-orthogonal polynomials

In this Note, we prove that all the components of a d-symmetric classical d-orthogonal are classical and in the case where the sequence is m-symmetric and d-orthogonal, we prove that the first component of an m-symmetric classical d-orthogonal is classical. That generalized the Douak and Maroni (1992) [8] results for the case m = d. Then we discuss, as far as we know, a new symmetric classical 3-PS. (C) 2011 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.