Divisor functions arising from q-series

Abstract

We consider some of the properties of divisor functions arising from q-series and theta functions. Using these we obtain several new identities involving divisor functions. On the other hand we prove a conjecture of Z. H. Sun concerning representations by the ternary quadratic form x(2) + y(2) + 3z(2), and also get an analogous result for x(2) + y(2) + 2z(2).