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(* Check effective names of mutual induction schemes *)
Inductive
even : nat->Prop :=
evenO : even O |
evenS : forall n, odd n -> even (S n)
with
odd : nat->Prop :=
oddS : forall n, even n -> odd (S n).
Scheme Even_induction := Minimality for even Sort Prop
with Odd_induction := Minimality for odd Sort Prop.
Theorem even_plus_four : forall n:nat, even n -> even (4+n).
Proof.
intros n H.
elim H using Even_induction with (P0 := fun n => odd (4+n));
simpl;repeat constructor;assumption.
Qed.
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