Definition semax_equiv {CS: compspecs} {Espec: OracleKind} c1 c2: Prop := forall Delta P Q, semax Delta P c1 Q <-> semax Delta P c2 Q.

Lemma unfold_Ssequence_unfold_Sseq_rel: forall c, unfold_Sseq_rel c (unfold_Ssequence c).