:: Homepage of José Hdz. Stgo. ::

Publications

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El truco de factorización favorito de Simon. Tzaloa: Revista de la Olimpiada Mexicana de Matemáticas, (2025), no. 2, pp. 1-18.
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Sobre un método para encontrar los polinomios de Darboux de un sistema dinámico. Tlamati Sabiduría, (2022), no. 14, pp. 11-15.
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La ecuación de Pell en las olimpiadas de matemáticas. Tzaloa: Revista de la Olimpiada Mexicana de Matemáticas, (2022), no. 3, pp. 1-25.
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Solving problems by looking at a discriminant. Mathematical Reflections, (2020), no. 4, pp. 1-10.
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With M. Z. Garaev & C. A. Díaz: Product of subsets of small intervals and points on exponential curves modulo a prime. Acta Arith., 193 (2020), no. 3, pp. 309-319.
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The group-theoretic analog of Kuratowski's closure-complement theorem. Amer. Math. Monthly, 126 (June-July 2019), no. 6, pp. 519-526, MR3956309.
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With M. Z. Garaev: A note on $n!$ modulo $p$. Monatsh. Math., 182 (January 2017), no. 1, pp. 23-31, MR3592116.
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With M.-C. Chang, J. Cilleruelo, M. Z. Garaev, I. E. Shparlinski, & A. Zumalacárregui: Points on curves in small boxes and applications. Michigan Math. J., 63 (2014), no. 3, pp. 503-534, MR3255689.
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Sobre las series de los recíprocos de los números poligonales. Misc. Matemática, (Octubre de 2012), núm. 55, págs. 1-11, MR3100379.

• With Daniel López-Aguayo & Leonardo Martínez-Sandoval: Un baúl de problemas olvidado (published electronically in universo.math): parte I, parte II, parte III, parte IV, parte V, parte VI

Preprints

– On prime numbers represented by forms with a discriminant whose class number is one.

Varia invención

El teorema de las seis exponenciales. One of the corollaries of the weak version of the famed Six Exponentials Theorem that I prove in this document is this: if $p_{1}$, $p_{2}$, and $p_{3}$ are three distinct prime numbers such that $p_{1}^{x}, p_{2}^{x}, p_{3}^{x} \in \mathbb{Z}$, then $x$ is a non-negative integer.

My conference in the Lecciones Matemáticas del PCCM (2016-2017) was based on this manuscript; that's the reason that you can find a copy of it within the Memorias Matemáticas del PCCM.
El teorema de Bolyai-Gerwien: notes on which a former student of mine based the talk that she delivered in an event organized by the Math. Dept. of UAGro sometime in the spring of 2015.
El Postulado de Bertrand: an expository note on Erdös' beautiful proof of Bertrand's Postulate.
Espacios vectoriales en problemas y soluciones by José Juan Rodríguez Vera.
NEW! (March 21, 2026) El algoritmo de Euclides y la ecuación diofántica lineal en dos variables by Ricardo Mandujano Zamora.

– Solutions to problems in Mathematical Reflections.

– Mehr Lösungen.

– My sequences in the OEIS:

– Answers to Prof. David E. Rowe's quiz on Gauss and Gaussian legends: they appeared in the pages of The Mathematical Intelligencer in 2016. Prof. Rowe was very kind to mention the answers that I sent to him in May 2016.

– On May 20 (2013), I sent a message to the editor of the Amer. Math. Monthly: it made it to the Editor's Endnotes of that year.

– A letter to the editor of Mathematical Reflections.

– Resources for the Olympiads (in Spanish).

– A wee bit of humor.

Favorite sites

• mathoverflow

• Apuntes Misceláneos (my blog) • Collected papers of Paul Erdös • fmat.cl

• Finding the class number of a neg. disc. • Kuratowski's Closure-Complement Cornucopia

• The Kurt Mahler Archive • Number Theory Web

Publications

Preprints

Varia invención

Favorite sites

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