Let P be given.
Assume H1.
We prove the intermediate claim L1: ∀alpha, ordinal alpha∀z, SNo zSNoLev z alphaP z.
Apply ordinal_ind to the current goal.
Let alpha be given.
Assume Ha: ordinal alpha.
Assume IH: ∀betaalpha, ∀z, SNo zSNoLev z betaP z.
Let z be given.
Assume Hz: SNo z.
Assume Hz2: SNoLev z alpha.
We will prove P z.
We prove the intermediate claim LLz: ordinal (SNoLev z).
An exact proof term for the current goal is SNoLev_ordinal z Hz.
Apply SNo_etaE z Hz to the current goal.
Let L and R be given.
Assume H2: SNoCutP L R.
Assume H3: ∀xL, SNoLev x SNoLev z.
Assume H4: ∀yR, SNoLev y SNoLev z.
Assume H5: z = SNoCut L R.
Apply H2 to the current goal.
Assume H6.
Apply H6 to the current goal.
Assume H6: ∀xL, SNo x.
Assume H7: ∀yR, SNo y.
Assume H8: ∀xL, ∀yR, x < y.
rewrite the current goal using H5 (from left to right).
We will prove P (SNoCut L R).
Apply H1 to the current goal.
We will prove SNoCutP L R.
An exact proof term for the current goal is H2.
We will prove ∀x, x LP x.
Let x be given.
Assume Hx: x L.
Apply IH (SNoLev z) Hz2 x to the current goal.
We will prove SNo x.
An exact proof term for the current goal is H6 x Hx.
We will prove SNoLev x SNoLev z.
An exact proof term for the current goal is H3 x Hx.
We will prove ∀y, y RP y.
Let y be given.
Assume Hy: y R.
Apply IH (SNoLev z) Hz2 y to the current goal.
We will prove SNo y.
An exact proof term for the current goal is H7 y Hy.
We will prove SNoLev y SNoLev z.
An exact proof term for the current goal is H4 y Hy.
Let z be given.
Assume Hz: SNo z.
We prove the intermediate claim L2: ordinal (ordsucc (SNoLev z)).
Apply ordinal_ordsucc to the current goal.
Apply SNoLev_ordinal to the current goal.
An exact proof term for the current goal is Hz.
Apply L1 (ordsucc (SNoLev z)) L2 z Hz to the current goal.
Apply ordsuccI2 to the current goal.