The theorem I quoted is a known result in complex analysis. That the function be analytic at the limit point is necessarily part of the hypothesis, since otherwise sin(1/z) would serve as a counterexample. -- Gene From: Warren D Smith <warren.wds@gmail.com> To: math-fun@mailman.xmission.com Sent: Monday, December 21, 2015 11:21 AM Subject: [math-fun] Periodic functions & Fourier transforms ? To Andy Latto, you are misunderstanding -- I did not claim EVERY countable set of points worked, I was claiming MANY countable sets of points work (in fact random points work with probability 1). Anyhow, my theorem seems obsoleted by Gareth McC's theorem, which shows any everywhere-dense countable point set works, and for merely-continuous functions. Finally, Andy Latto's sort of counterexample DOES work to kill some variants of Eugene Salamin's claimed theorem. -- Warren D. Smith http://RangeVoting.org <-- add your endorsement (by clicking "endorse" as 1st step)