#P: A Language for Counting

A set is an unordered (unless otherwise specified) collection of elements of the same type, usually expressed using the following notation: {elem1, elem2, elem3, . . .} A tuple is an ordered collection of elements, not necessarily of the same type, expressed using the following notation: (elem1, elem2, elem3, . . .) Most of the times, we don’t give too much attention to the actual elements themselves, rather, when it comes to sets for instance, we want to make sure that all elements have the same type. To enforce this, we have a special syntax when constructing representations of sets. This will be described later.