The Hungarian mathematician Jànos Bolyai, who, completely independently of the Russian Nikolai Lobachevsky, developed non-Euclidean hyperbolic geometry was born in Cluj (when it was known as Kolozsvár in the Hungarian empire). I'm pleased to see Cluj has a street named after Bolyai.

Yes - I migrated all my different accounts over here last time I thought Twitter might die. It has taken sometime to get a critical mass of people who I interact with, but there does seem to have been a bit of impetus here over recent days.

I remember, as a child, learning the answer to that question from reading Martin Gardner's Mathematical Games column in Scientific American.