Wreath Product Generalizations of the Triple (S2n,Hn,ϕ)(S_{2n},H_{n},\phi) and Their Spherical Functions

The symmetric group $S_{2n}$ and the hyperoctaheadral group $H_{n}$ is a Gelfand triple for an arbitrary linear representation $\phi$ of $H_{n}$. Their $\phi$-spherical functions can be caught as transition matrix between suitable symmetric functions and the power sums. We generalize this triplet in the term of wreath product. It is shown that our triplet are always to be a Gelfand triple. Furthermore we study the relation between their spherical functions and multi-partition version of the ring of symmetric functions.Comment: 25 page

Orthogonality Relations for Multivariate Krawtchouk Polynomials

The orthogonality relations of multivariate Krawtchouk polynomials are discussed. In case of two variables, the necessary and sufficient conditions of orthogonality is given by Gr\"unbaum and Rahman in [SIGMA 6 (2010), 090, 12 pages, arXiv:1007.4327]. In this study, a simple proof of the necessary and sufficient condition of orthogonality is given for a general case

Orthogonal polynomials arising from the wreath products of a dihedral group with a symmetric group

AbstractSome classes of orthogonal polynomials are discussed in this paper which are expressed in terms of (n+1,m+1)-hypergeometric functions. The orthogonality comes from that of zonal spherical functions of certain Gelfand pairs

Mixed expansion formula for the rectangular Schur functions and the affine Lie algebra A_1^(1)

Formulas are obtained that express the Schur S-functions indexed by Young diagrams of rectangular shape as linear combinations of "mixed" products of Schur's S- and Q-functions. The proof is achieved by using representations of the affine Lie algebra of type A_1^{(1)}. A realization of the basic representation that is of ``D_2^{(2)}''-type plays the central role.Comment: 21page