• La ecuación de Pell en las olimpiadas de matemáticas.
Tzaloa: Revista de la Olimpiada Mexicana de Matemáticas (2022), no. 3, pp. 1-25.
• Solving problems by looking at a discriminant.
Mathematical Reflections (2020), no. 4, pp. 1-10.
• 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.
• The group-theoretic analog of Kuratowski's closure-complement
theorem. Amer. Math. Monthly 126 (June-July 2019), no. 6, pp. 519-526, MR3956309.
• With M. Z. Garaev: A note on $n!$ modulo $p$. Monatsh. Math.
182 (January 2017), no. 1, pp. 23-31, MR3592116.
• 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.
• 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
• On prime numbers represented by forms with a discriminant whose class number is one.
— Some manuscripts:
— Solutions to problems in Mathematical Reflections.
— Mehr Lösungen.
— My sequences in the OEIS: A269665,
A270441,
A273217,
A295866,
A295868,
A299028,
A299030,
A347933
— 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.
— NEW! (Jan. 9th, 2023) Resources for the Olympiads (in Spanish).
• mathoverflow
• Apuntes Misceláneos (my blog)
• Collected papers of Paul Erdös
• El i$\pi$acional
• fmat.cl
• Finding the class number of a neg. disc.
• Kuratowski's Closure-Complement Cornucopia
• The Kurt Mahler Archive
• Number Theory Web
• NU Problem-Solving Group
• Ponder This!
Mathematicians
Periodicals
A reward check I received from Prof. Donald Knuth a few years ago.
© 2010-2022
Last updated on Dec. 13th, 2022