Ring theory MOC Centre of a rng The centre Z(π ) of a rng π is the subrng consisting of all elements of π that commute with every other element, i.e. Z(π ) ={π βπ β£ππ₯ =π₯π βπ₯ βπ }. ring This is entirely analogous with the centre of a group. Properties The centre is necessarily a commutative ring If π is a ring then 1 βπ(π ) tidy | en | SemBr