Realizations with five subsquares

Abstract

Given an integer partition $(h_1,h_2,\dots,h_k)$ of $n$, is it possible to find an order $n$ latin square with $k$ disjoint subsquares of orders $h_1,\dots,h_k$? This question was posed by L.Fuchs and is only partially solved. Existence has been determined in general when $k\leq 4$, and in this paper we will complete the case when $k=5$. We also prove some less general results for partitions with $k=5$.