\rhdThe \rhd symbol is used to denote a binary operation or relation, often representing a form of product or action in algebraic structures, such as semigroups or group actions.
A binary operation where element 'a' acts on element 'b' to produce 'c'.
a \rhd b = cSequential application of the operation, showing associativity.
x \rhd y \rhd zA group action of G on a set X.
G \rhd X