Index of notation/P

Expression	Status	Meanings	See also
$p$	current	Prime numbers, projective functions (along with $\pi$), vector points (typically $p,q,r$), representing rational numbers as $\frac{p}{q}$
$P$	dangerous	Sometimes used for probability measures, the notation $\mathbb{P}$ is recommended for these.
$\mathbb{P}$	current	See P (notation) for more information. Typically: $\mathbb{P}$ denotes a probability function almost always. However I have seen: $\mathbb{P}$ to denote set of predicates in order theory TODO: Introduction to Lattices and Order - p2 for details, bottom of page Also used in denoting the real projective spaces, eg $\mathbb{RP}^2$ for the real projective plane ($P\mathbb{R}^2$ is also used) TODO: Find refs
$\mathcal{P}(X)$	current	Power set, I have seen no other meaning for $\mathcal{P}(X)$ (where $X$ is a set) however I have seen the notation: $2^X:=\mathcal{P}(X)$ used to denote powerset