2026/07/24 by Gyula Károlyi, Jozsef Solymosi
Mathematics · #math.CO #math.NT
Let F(n) be the largest size of a subset of \0,1,…,n-1\2 containing no nondegenerate isosceles right triangle. We give a modified Salem--Spencer-type construction over the Gaussian integers showing that F(n)=Ω(n1.3). The best known upper bound is F(n)≪ n2/(log n)1+c for some absolute constant c>0, so there is still a large gap between the bounds.