One of the stranger symbols to ever cross the pages of a mathematician is the three-legged pi symbol, advocated by Bob Palais in his piece π is wrong as a symbol for 2π (and as opposed to using the Greek letter tau for that purpose).

Some examples of three-legged pi in action:

Is there a standard (La)TeX way to get this symbol? I had a look on google, detexify, ctan and symbols-a4, and didn't get anywhere.

(Also: I don't particularly intend to use it, and definitely not in a publication. But it'd be nice to have around.)

  • Wikipedia's Tau proposal prints this as \pi\!\;\!\!\!\pi. Not pretty. – Werner May 30 '16 at 18:31
  • This rather looks like a handwritten cyrillic t (looking as some kind of a handwritten Latin m) – user31729 May 30 '16 at 18:32
  • @Werner: Nice idea, but the kerning is wrong -- I just tried it (at least with standard fonts) – user31729 May 30 '16 at 18:33
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    it is hard to read 3 legged pi, vs. 2*pi. So I think for readability alone, it is bad idea to use this symbol in actual papers. – Nasser May 30 '16 at 18:51
  • @Nasser I'm glad you agree with the question. – E.P. May 30 '16 at 18:53

Based on the idea of Palai's definition, given by Nessiesson's answer - how about this?


\newcommand{\twopi}{\pi \mskip-6.6mu \reflectbox{$\tau$}}

enter image description here

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According to Palais' own website, it seems that the macro \def \newpi{{\pi\mskip -7.8 mu \pi}} was used.

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    This looks like a four-legged pi – user31729 May 30 '16 at 18:41
  • Yeah, that's pretty close, but it's font-dependent. On my system it produces this, which isn't quite there either. (Under lmodern.) – E.P. May 30 '16 at 18:44

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