A Sharp Fourier Inequality and the Epanechnikov Kernel

Sean Richardson

We consider functions $f:\mathbb{Z}\to \mathbb{R}$ and kernels $u:\{-n,\cdots ,n\}\to \mathbb{R}$ normalized by ${\sum }_{\ell =-n}^{n}u(\ell )=1$, making the convolution $u \…