The Hörmander--Bernhardsson extremal function

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

We characterize the function $\ddot{I}†$ of minimal $L^1$ norm among all functions $f$ of exponential type at most $\ddot{I}€$ for which $f(0)=1$. This function, studied by Hörmander and Bernha…