Rank and Crank Moments for Partitions without Repeated Odd Parts

Abstract

Using quasimodular forms with respect to $\Gamma_0(4)$ we find exact relations between the M2-rank for partitions without repeated odd parts and three residual cranks. From these identities we are able to deduce various congruences mod 3 and 5 between the rank and crank moments. In turn, these congruences give congruences for $M2spt(n)$, the number of occurrences of smallest parts in the partitions of $n$ with smallest part even and without repeated odd parts, and for the higher order analog $M2spt_2(n)$.