Arthur B.
In particular, Nicușor solved the infamous problem 6 from the 1988 IMO. Terence Tao competed that year and didn't solve it, though to be fair he was 13 years old at the time.
Arthur B.
He also holds a math PhD from ENS Paris. He might be the smartest head of state at this point. There's way, way, more to being a competent head of state than being smart, but this is pretty bullish for Romania.
