The Hörmander--Bernhardsson extremal function: A preliminary study

Andriy Bondarenko, Joaquim Ortega-Cerdà, Danylo Radchenko +1

We study the function ${\phi }_1$ of minimal $L^1$ norm among all functions $f$ of exponential type at most $\pi$ for which $f(0)=1$. This function, first studied by Hörmander and Bernhard…