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xkcd #3184: Funny Numbers
(imgs.xkcd.com)
Title text:
In 1899, people were walking around shouting '23' at each other and laughing, and confused reporters were writing articles trying to figure out what it meant.
Transcript:
Transcript will show once it’s been added to explainxkcd.com
Source: https://xkcd.com/3184/
Which works in base 13!
Im 93% sure that 6*9 doesnt equal 42 in base 6227020800
which, when a mathemagician occasionally asked adams about it, he would respond along the lines of "oh fuck"