Section dio_rel_finite_conj.
Notation "∑" := (msum plus 0).
Definition df_true := proj1_sig dio_rel_True.
Fact df_true_size : df_size df_true = 4.
Fact df_mconj_spec n f ν : df_pred (df_mconj n f) ν <-> forall i, i < n -> df_pred (f i) ν.

Lemma dio_rel_finite_conj n (R : nat -> (nat -> nat) -> Prop) :
(forall i, i < n -> 𝔻R (R i))
-> 𝔻R (fun ν => forall i, i < n -> R i ν).