Overpartitions and class numbers of binary quadratic forms
Overpartitions and class numbers of binary quadratic forms
We show that the Zagier–Eisenstein series shares its nonholomorphic part with certain weak Maass forms whose holomorphic parts are generating functions for overpartition rank differences. This has a number of consequences, including exact formulas, asymptotics, and congruences for the rank differences as well as q -series identities of the mock …