Solution (source code)

= Solution

Risk-neutral valuation gives
$$
e^{-rT}\mathbb E[(S_T-K)^+]
=S_0\mathbb E\left[\left(e^{-\sigma^2T/2+\sigma\sqrt T Z}
-\frac{Ke^{-rT}}{S_0}\right)^+\right].
$$
With $v=\sigma^2T$ and $m=Ke^{-rT}/S_0$, this is exactly
$$
\boxed{S_0F(v,m).}
$$