Fejer 1900: Cesaro mean F_n = sum_{k<=n} (1 - k/n) e^{ikx} converges uniformly to f for f continuous + 2pi-periodic; salvages divergent Fourier series.
Fejer 1900: Cesaro mean F_n = sum_{k<=n} (1 - k/n) e^{ikx} converges uniformly to f for f continuous + 2pi-periodic; salvages divergent Fourier series.