4 papers
math.NT2026
Infinite families of Diophantine quadruples in in the remaining exceptional congruence classes
Andrej Dujella, Ivan Soldo
We continue the study of -quadruples in the ring . Motivated by the earlier classification due to the authors and by the subsequent partial results for…
math.NT2026
Differences of squares of upper-triangular integer matrices
Andrej Dujella, Zrinka FranuÅ¡iÄ
We consider the problem of characterizing upper-triangular matrices which can be represented in the form with u…
math.NT2026
Seven squares from three numbers
Andrej Dujella, Matija Kazalicki, Vinko PetriÄeviÄ
We study triples {a,b,c} of distinct nonzero rational numbers such that a+1,b+1,c+1,ab+1,ac+1,bc+1 and abc+1 are all perfect squares. We prove that there exist infinitely many such…
math.NT2024
Asymptotics of -pairs and triples via -functions of Dirichlet charaters
Nikola Adžaga, Goran DražiÄ, Andrej Dujella +1
Let be an integer. A --tuple is a set of distinct positive integers such that is a perfect square for all $1 \leq i < j \leq…