Let X and Tx be given.
Apply Hexm to the current goal.
Let m be given.
Assume Hmpack.
We prove the intermediate
claim HmO:
m ∈ ω.
We use m to witness the existential quantifier.
Apply andI to the current goal.
Apply andI to the current goal.
An exact proof term for the current goal is HTx.
An exact proof term for the current goal is HmO.
An exact proof term for the current goal is Hmprop.
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