\RThe \R command in LaTeX is used to produce the letter 'R' with a ring accent above it, often used in mathematical and scientific contexts to denote specific sets or operations.
The set of real numbers, often denoted by a bold or double-struck R.
\RThe n-dimensional Euclidean space, representing all n-tuples of real numbers.
\R^nA function f that maps real numbers to real numbers.
f: \R \to \R