Let alpha, g and h be given.
We will prove G alpha g = G alpha h.
We will
prove (If_ii (ordinal alpha) (λz : set ⇒ if z ∈ SNoS_ (ordsucc alpha) then F z (λw ⇒ g (SNoLev w) w) else default) (λz : set ⇒ default)) = (If_ii (ordinal alpha) (λz : set ⇒ if z ∈ SNoS_ (ordsucc alpha) then F z (λw ⇒ h (SNoLev w) w) else default) (λz : set ⇒ default)).
Apply xm (ordinal alpha) to the current goal.
Assume H1: ordinal alpha.
rewrite the current goal using
If_ii_1 (ordinal alpha) (λz ⇒ if z ∈ SNoS_ (ordsucc alpha) then F z (λw ⇒ h (SNoLev w) w) else default) (λz : set ⇒ default) H1 (from left to right).
rewrite the current goal using
If_ii_1 (ordinal alpha) (λz ⇒ if z ∈ SNoS_ (ordsucc alpha) then F z (λw ⇒ g (SNoLev w) w) else default) (λz : set ⇒ default) H1 (from left to right).
We will
prove (λz : set ⇒ if z ∈ SNoS_ (ordsucc alpha) then F z (λw ⇒ g (SNoLev w) w) else default) = (λz : set ⇒ if z ∈ SNoS_ (ordsucc alpha) then F z (λw ⇒ h (SNoLev w) w) else default).
Apply func_ext set set to the current goal.
Let z be given.
We will
prove (if z ∈ SNoS_ (ordsucc alpha) then F z (λw ⇒ g (SNoLev w) w) else default) = (if z ∈ SNoS_ (ordsucc alpha) then F z (λw ⇒ h (SNoLev w) w) else default).
Apply xm (z ∈ SNoS_ (ordsucc alpha)) to the current goal.
rewrite the current goal using
If_i_1 (z ∈ SNoS_ (ordsucc alpha)) (F z (λw ⇒ g (SNoLev w) w)) default Hz (from left to right).
rewrite the current goal using
If_i_1 (z ∈ SNoS_ (ordsucc alpha)) (F z (λw ⇒ h (SNoLev w) w)) default Hz (from left to right).
We will
prove F z (λw ⇒ g (SNoLev w) w) = F z (λw ⇒ h (SNoLev w) w).
We prove the intermediate claim Lsa: ordinal (ordsucc alpha).
An exact proof term for the current goal is ordinal_ordsucc alpha H1.
Apply SNoS_E2 (ordsucc alpha) Lsa z Hz to the current goal.
We will
prove F z (λw ⇒ g (SNoLev w) w) = F z (λw ⇒ h (SNoLev w) w).
Apply Fr to the current goal.
An exact proof term for the current goal is Hz3.
Let w be given.
We prove the intermediate
claim LLw:
SNoLev w ∈ alpha.
Apply ordsuccE alpha (SNoLev z) Hz1 to the current goal.
Apply H1 to the current goal.
Assume Ha1 _.
An
exact proof term for the current goal is
Ha1 (SNoLev z) H2 (SNoLev w) Hw1.
rewrite the current goal using H2 (from right to left).
An exact proof term for the current goal is Hw1.
rewrite the current goal using
Hgh (SNoLev w) LLw (from left to right).
Use reflexivity.
rewrite the current goal using
If_i_0 (z ∈ SNoS_ (ordsucc alpha)) (F z (λw ⇒ h (SNoLev w) w)) default Hz (from left to right).
An
exact proof term for the current goal is
If_i_0 (z ∈ SNoS_ (ordsucc alpha)) (F z (λw ⇒ g (SNoLev w) w)) default Hz.
Assume H1: ¬ ordinal alpha.
rewrite the current goal using
If_ii_0 (ordinal alpha) (λz ⇒ if z ∈ SNoS_ (ordsucc alpha) then F z (λw ⇒ h (SNoLev w) w) else default) (λz : set ⇒ default) H1 (from left to right).
An
exact proof term for the current goal is
If_ii_0 (ordinal alpha) (λz ⇒ if z ∈ SNoS_ (ordsucc alpha) then F z (λw ⇒ g (SNoLev w) w) else default) (λz : set ⇒ default) H1.