Let $f_n: \mathbb{R} \to \mathbb{R}$ be defined as follows:
$f_n$ is even.
$f_n(0) = \frac{1}{2}$
$f_n(x) = 0$ if $0
$f_n(x) = 1$ if $x> 2/n$
$f_n$ is linear on $(\frac{1}{n}, \frac{2}{n})$, and continuous on $\mathbb{R} - \{0\}$
I think each $f_n$ is USC, but the pointwise liminf is not. How am I wrong?