Email Gateway (Mar 16 2022 at 11:44): Email Gateway (Mar 16 2022 at 11:44):From: Lawrence Paulson <lp15@cam.ac.uk>
I’m happy to announce a new entry by Manuel Eberl:
A Proof from THE BOOK: The Partial Fraction Expansion of the Cotangent
In this article, I formalise a proof from THE BOOK; namely a formula that was called ‘one of the most beautiful formulas involving elementary functions’. The proof uses Herglotz's trick to show the real case and analytic continuation for the complex case.
It is small, but perfectly formed. Now online at https://www.isa-afp.org/entries/Cotangent_PFD_Formula.html
Larry
Last updated: Jan 04 2025 at 20:18 UTC