Equidistribution and inequalities for partitions into powers

If $p_k(a,m,n)$ denotes the number of partitions of $n$ into $k$th powers with a number of parts that is congruent to $a$ modulo $m,$ then $p_2(0,2,n)\sim p_2(1,2,n)$ and the sign of the difference $p_2(0,2,n)- p_k(1,2,n)$ alternates with the parity of $n,$ as proven by recent work of the author (2020). In this paper, we place the problem in a broader framework. By analytic arguments using the circle method and Gauss sums estimates, we show that the same results hold for any $k\ge2.$ By combinatorial arguments, we show that the sign of the difference $p_k(0,2,n)- p_k(1,2,n)$ depends on the parity of $n$ for a larger class of partitions.