proposition: Lemma dirr_inj : injective (@dchi G).
proof: Proof. case=> b1 i1 [b2 i2] /eqP; rewrite eq_scaled_irr (inj_eq signr_inj) /=. by rewrite signr_eq0 -xpair_eqE => /eqP. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq path) mathcomp(div choice fintype tuple finfun bigop prime order) mathcomp(ssralg poly finset fingroup morphism perm) mathcomp(automorphism quotient finalg action gproduct) mathcomp(zmodp commutator cyclic center pgroup sylow) mathcomp(frobenius vector ssrnum ssrint archimedean intdiv) mathcomp(algC algnum classfun character integral_char)