Atom - Œc - Unordered Pairs

Characters: Π, c

Tags: miscellaneous , math , array , combinatorics

Arity: monadic

This atom is monadic, which means it takes one argument.

Functionality

All unordered pairs without replacement (i.e. without pairing an element to itself).

Details

For example, 4R Œc/code> returns [[1, 2], [1, 3], [1, 4], [2, 3], [2, 4], [3, 4]] - [1, 1], [2, 2], etc. are not included.

Synonyms

This atom should work roughly the same way as or very similarly in concept to the following code snippets (some edge case exceptions may exist):