#1292: Pi vs. Tau

XKCD comic, described below.
Transcript

[[On the left is a "forbidden"-style slashed circle with the Pi symbol, captioned "Pi". On the right is a "forbidden-style slashed circle with "2π", captioned "Tau". In the middle it reads "1.5π", captioned "Pau".]] A compromise solution to the Pi Tau dispute

Conveniently approximated as e+2, Pau is commonly known as the Devil's Ratio (because in the octal expansion, '666' appears four times in the first 200 digits while no other run of 3+ digits appears more than once.)

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