I know there are people who complain about π Day and τ Day only working in a Month/Day format
Some time ago I jokingly introduced a contender "sampi":
ϡ ≡ π/2 ≡ τ/4
So at least we could dedicate 15/7 as Sampi Day (ignoring the zero), celebrating the angle of orthogonality. And there are several notable properties of ϡ that (arguably) aren't as elegant with π or τ...
Maybe Mathstodon should have #SampiDay on 15th July?
@btcprox that's exactly a week before Pi Approximation Day on 22/7.
A Mastodon instance for maths people. The kind of people who make \(\pi z^2 \times a\) jokes.
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