A Survey of Alternative Solutions to the Congruum Problem

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteur principal: Johnson, Nathanael
Format: Preprint
Publié: 2025
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866913823666995200
author Johnson, Nathanael
author_facet Johnson, Nathanael
contents A congruum was first defined by Leonardo Pisano in 1225 and it is defined as the common difference in an arithmetic progression of three perfect squares. Later that year in his book Liber Quadratorum, Pisano proved that congruums can never perfect squares themselves, a finding that was later revisited by Pierre de Fermat in 1670. His proof is now known as Fermat's Right Triangle Theorem. In this paper, four alternative proofs to Pisano's original proof are demonstrated and offered with each proof requiring a different scope of mathematical knowledge. The proofs are by direct Diophantine analysis, parameterization of differences, Heronian triangle construction, and infinite descent. In showing these proofs, it is demonstrated that there are alternatives to the method of decomposing perfect squares as sums of odd numbers as Pisano did in his proof in 1225.
format Preprint
id arxiv_https___arxiv_org_abs_2505_03752
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle A Survey of Alternative Solutions to the Congruum Problem
Johnson, Nathanael
General Mathematics
11D09
A congruum was first defined by Leonardo Pisano in 1225 and it is defined as the common difference in an arithmetic progression of three perfect squares. Later that year in his book Liber Quadratorum, Pisano proved that congruums can never perfect squares themselves, a finding that was later revisited by Pierre de Fermat in 1670. His proof is now known as Fermat's Right Triangle Theorem. In this paper, four alternative proofs to Pisano's original proof are demonstrated and offered with each proof requiring a different scope of mathematical knowledge. The proofs are by direct Diophantine analysis, parameterization of differences, Heronian triangle construction, and infinite descent. In showing these proofs, it is demonstrated that there are alternatives to the method of decomposing perfect squares as sums of odd numbers as Pisano did in his proof in 1225.
title A Survey of Alternative Solutions to the Congruum Problem
topic General Mathematics
11D09
url https://arxiv.org/abs/2505.03752