We prove several results dealing with various counting functions for partitions of an integer into four squares of equal parity. Some are easy consequences of earlier work, but two are new and surprising. That is, we show that the number of partitions of \(72n+ 60\) into four odd squares (distinct or not) is even.
Citation
Michael D.Hirschhorn, James A.Sellers. Further Results for Partitions Into Four Squares of Equal Parity[J], Ars Combinatoria, Volume 076. 33-45. .