I was going to append this to @chwala 's thread here , but thought it deserved a new thread. For ##n \geq 1##, define fn:[0,1]R:x{1x=0,n(1nx)x(0,1n],0x(1n,1].f_n : [0,1] \to \mathbb{R} : x \mapsto \begin{cases} 1 & x = 0, \\ n(1 - nx) & x \in (0, \tfrac 1n], \\ 0 & x \in (\tfrac 1n, 1]. \end{cases} (Note that ##f_n## is... Read more