Let N be a normal subgroup of a finite group G and V be a fixed finite-dimensional G-module. The Poincare series for the multiplicities of induced modules and restriction modules in the tensor algebra T(V ) = ⊕k≥0V ⊗k are studied in connection with the McKay-Slodowy correspondence. In particular, it is shown that the closed formulas for the Poincare series associated with the distinguished pairs of subgroups of SU2 give rise to the exponents of all untwisted and twisted affine Lie algebras except A2n¬(2). This talk is based on the joint work with Prof. Jing and Danxia Wang.