Monthly Archives: May 2018

A sequence of kernels $K_n(x)$ on $[-\pi, \pi]$ is called *good* if $\frac{1}{2\pi} \int_{-\pi}^\pi K_n(x) \, dx = 1$, $\frac{1}{2\pi} \int_{-\pi}^\pi |K_n(x)| \, dx$ is bounded, and $\frac{1}{2\pi} \int_{|x| \geq c} |K_n(x)| \, dx \to 0$ as $n \to \infty$ … Continue reading →