Weierstrass p
In mathematics, the Weierstrass p (℘, ), also called pe, is used for Weierstrass's elliptic functions. It is occasionally used for the power set, although for that purpose a cursive capital, rather than lower-case, p is more widespread. It is named after the German mathematician Karl Weierstrass.
Its Unicode code point is U+2118 ℘ SCRIPT CAPITAL P (HTML ℘ · ℘). The naming is incorrect, because it is always a lowercase letter, but this error is not corrected in later versions in order to keep the Unicode standard stable. The TeX code for this character is \wp.
Starting with Unicode 3.0.1, a separate, capital symbol is available for power set, namely U+1D4AB ...
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