We derive a new explicit formula in terms of sums over graphs for the
n-point correlation functions of general formal weighted double Hurwitz
numbers coming from the Kadomtsev-Petviashvili tau functions of hypergeometric
type (also known as Orlov-Scherbin partition functions). Notably, we use the
change of variables suggested by the associated spectral curve, and our formula
turns out to be a polynomial expression in a certain small set of formal
functions defined on the spectral curve.Comment: 35 pages; statements regarding the ℏ-deformations were
corrected; further minor change