proposition: Lemma neq0Ci : 'i != 0 :> C.
proof: Proof. by apply: contraNneq nonRealCi => ->. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(ssrAC div fintype path bigop order finset fingroup) mathcomp(ssralg poly)