Ring theory MOC Centre of a rng The centre Z(𝑅) of a rng 𝑅 is the subrng consisting of all elements of 𝑅 that commute with every other element, i.e. Z(𝑅) ={𝑎 ∈𝑅 ∣𝑎𝑥 =𝑥𝑎 ∀𝑥 ∈𝑅}. #m/def/ring This is entirely analogous with the centre of a group. Properties The centre is necessarily a commutative ring If 𝑅 is a ring then 1 ∈𝑍(𝑅) #state/tidy | #lang/en | #SemBr