  In this paper, we consider the $q \rightarrow 0$ limit of the deformed
Virasoro algebra and that of the level 1, 2 representation of Ding-Iohara-Miki
algebra. Moreover, 5D AGT correspondence at this limit is discussed. This
specialization corresponds to the limit from Macdonalds functions to
Hall-Littlewood functions. Using the theory of Hall-Littlewood functions, some
problems are solved. For example, the simplest case of 5D AGT conjectures is
proven at this limit, and we obtain a formula for the 4-point correlation
function of a certain operator.
