Let x be given.
Assume Hx.
Let p be given.
Assume Hp.
Assume H1 H2.
Apply H2 to the current goal.
Assume H2.
Apply H2 to the current goal.
Assume H4.
Assume H1a H1b H1c H1d.
We prove the intermediate
claim L1:
x < ω.
We prove the intermediate
claim L1a:
x ≤ ω.
An exact proof term for the current goal is H1a.
Assume H.
An exact proof term for the current goal is H.
An exact proof term for the current goal is H2 H.
We prove the intermediate
claim L2:
- ω < x.
We prove the intermediate
claim L2a:
- ω ≤ x.
An exact proof term for the current goal is H1a.
Assume H.
An exact proof term for the current goal is H.
Apply H3 to the current goal.
Use symmetry.
An exact proof term for the current goal is H.
An exact proof term for the current goal is Hp H1c H1a H1 L2 L1 H4 L3.
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