Certain classes of polynomial expansions and multiplication formulas

The authors first present a class of expansions in a series of Bernoulli polyomials and then show how this general result can be applied to yield various (known or new) polynomial expansions. The corresponding expansion problem involving the Euler polynomials is then considered in an analogous manner. Several general multiplication formulas, involving (for example) certain families of generalized hypergeometric polynomials, are also investigated in the context especially of the classical Jacobi, Laguerre, and other related orthogonal polynomials.