In group theory exponential notation such as x^f (picture a superscript, like x^f) or composing on the right (x)f are not altogether uncommon. It's pa

In group theory exponential notation such as x^f (picture a superscript, like x^f) or composing on the right (x)f are not altogether uncommon. It's particulary convenient for homomorphisms or the action of a group on a set. Some category theorists of the mathematical kind, not the computer science kind, (i.e the kind that cares most deeply about homological algebra) also like to compose on the right, so that you can write function composition in the order that you diagram-chase.