The Method of Weighted Words Revisited

Alladi and Gordon introduced the method of weighted words in 1993 to prove a refinement and generalisation of Schur’s partition identity. Together with Andrews, they later used it to refine Capparelli’s and Göllnitz’ identities too. In this paper, we present a new variant of this method, which can be used to study more complicated partition identities, and apply it to prove refinements and generalisations of three partition identities. The first one, Siladić’s theorem (2002), comes from vertex operator algebras. The second one, a conjectural identity of Primc (1999), comes from crystal base theory. The last one is a very general identity about coloured overpartitions which generalises and unifies several generalisations of Schur’s theorem due to Alladi-Gordon, Andrews, Corteel-Lovejoy, Lovejoy and the author.