1Department of Mathematics and Physics, “Fan S. Noli” University, Korçë, Albania
2Department of Mathematics Engineering, Polytechnic University, Tirana, Albania
Turkish Journal of Analysis and Number Theory.
2026,
Vol. 14 No. 1, 23-28
DOI: 10.12691/tjant-14-1-3
Copyright © 2026 Science and Education PublishingCite this paper: Arto Adili, Adrian Naço, Lorena Kelo. An Elementary Method for Determining the Quadratic Character of -1, 2, 3 and 5 Modulo Primes.
Turkish Journal of Analysis and Number Theory. 2026; 14(1):23-28. doi: 10.12691/tjant-14-1-3.
Correspondence to: Arto Adili, Department of Mathematics and Physics, “Fan S. Noli” University, Korçë, Albania. Email:
aadili@unkorce.edu.alAbstract
We provide elementary proofs of the classical quadratic-residue criteria for -1, 2, 3, and 5 modulo odd primes. In addition, we determine the quadratic character of the integers a and b in the prime representations p=a2+b2 and p=a2+2b2. These results further illustrate the relationship between quadratic residues and binary quadratic forms.
Keywords