Fact Cint_key : pred_key Cint.Fact Cint_subring : subring_closed Cint.Canonical Cint_keyed := KeyedPred Cint_key.Canonical Cint_opprPred := OpprPred Cint_subring.Canonical Cint_addrPred := AddrPred Cint_subring.Canonical Cint_mulrPred := MulrPred Cint_subring.Canonical Cint_zmodPred := ZmodPred Cint_subring.Canonical Cint_semiringPred := SemiringPred Cint_subring.Canonical Cint_smulrPred := SmulrPred Cint_subring.Canonical Cint_subringPred := SubringPred Cint_subring.

Lemma truncC0Pn x : reflect (truncC x = 0%N) (~~ (1 <= x)).