Sets of integers avoiding congruent subsets

We study the sets of integers A that avoid g congruent h-subsets (the Ch[g] sets, for short), as well as the variant in which the h-subsets are pairwise disjoint (the weak-Ch[g] sets). For h=g=2 these are the Sidon sets and the weak-Sidon sets respectively.We refine and improve upon several results by Erdős and Harzheim.