Let m be given.
Assume IH: P m.
We prove the intermediate
claim Hsub:
ordsucc m ⊆ n.
We prove the intermediate
claim HmInN:
m ∈ n.
An
exact proof term for the current goal is
(Hsub m (ordsuccI2 m)).
We prove the intermediate
claim HmInSuccN:
m ∈ ordsucc n.
An
exact proof term for the current goal is
(ordsuccI1 n m HmInN).
We prove the intermediate
claim HrS:
SNo r.
An
exact proof term for the current goal is
(real_SNo r HrR).
An exact proof term for the current goal is (HtermR m HmInN).
An exact proof term for the current goal is (IH HmInSuccN).
Apply andI to the current goal.
Apply andI to the current goal.
rewrite the current goal using
(nat_primrec_S 0 step m HmNat) (from left to right).
rewrite the current goal using
(nat_primrec_S 0 step' m HmNat) (from left to right).
rewrite the current goal using
(nat_primrec_S 0 step m HmNat) (from left to right).
rewrite the current goal using
(nat_primrec_S 0 step' m HmNat) (from left to right).
rewrite the current goal using Hlhs (from left to right).
rewrite the current goal using HeqIH (from left to right).
Use reflexivity.