Jesús Guillera

Jesús Guillera (31 December 1955 – 9 February 2026) was a Spanish mathematician who specialised in number theory, best known for his work on Ramanujan-type series for calculating the mathematical constant π. Largely self-taught in advanced mathematics, he later earned a doctorate from the University of Zaragoza and since then published extensively on hypergeometric identities, WZ-pairs, and related topics in analytic number theory.