Generalized Brézin–Gross–Witten tau-function as a hypergeometric solution of the BKP hierarchy

In this paper, we prove that the generalized Brézin–Gross– Witten tau-function is a hypergeometric solution of BKP hierarchy with simple weight generating function. We claim it describes spin version strictly monotone Hurwitz numbers. A family tau-functions hierarchy, corresponding to rational functions, investigated. particular, cut-and-join operators are constructed, and explicit description Sato Grassmannian points derived. Representatives can be associated interesting families numbers including