A Variation on Selberg's Approximation Problem
  Let $\alpha\in\mathbb{C}$ in the upper half-plane and let $I$ be an interval. We construct an analogue of Selberg's majorant of the characteristic function of $I$ that vanishes at the point $\alpha$. The construction is based on the solution to an extremal problem with positivity and interpolation constraints. 
Michael Kelly
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