As interesting as developments in chemistry are, I'm also wondering how and when computers will come about. In OTL, Andrei Kolmogorov could, despite working in the Soviet Union, travel internationally and publish his works. It is already known that TTL there will be restrictions on trade and on the flow of information for many decades, until the 1980s at the latest. The effects on mathematics... well, concurrent independent invention is hardly unprecedented in the field, but every mathematical tradition having to arrive at every theory independently, and not knowing how to interpret references in imported texts, all that will slow things down. We could go for what happened OTL and have a large number of mathematicians flee to a single country and cooperate there-- or maybe, due to its unique in-between status, Danubia ends up becoming a venue for discreet meetups and conferences, people being dropped off in Czechosilesia or the Balkan border with the Eternal State and returning home with new notes in hand. It would be really funny if mathematicians took on this kind of Freemason-ish/First International air, considering themselves more loyal to their noble shared mission than to the competing governments that would stand in their way, and meeting in multinational cabals to... I don't know, listen to each other talk about topology.
At the very least, for every country to get computers at around the same time one would hope that the rules of mathematical logic, of Boole's binary system and Frege's predicate logic, have been created and propagated in the previous century. This seems likely, because although this world is late to electricity the Optel system already got people thinking about these questions of how to construct meaningful codes out of as few symbols as possible. It's possible that mechanical difference/analytic engines have already been built around the world.
Lastly, a interesting video: