Assume H1.
Apply H1 to the current goal.
We will
prove PNoLe alpha p gamma r.
rewrite the current goal using H1a (from left to right).
We prove the intermediate
claim L1:
PNoEq_ beta p q.
rewrite the current goal using H1a (from right to left).
An exact proof term for the current goal is H1b.
An
exact proof term for the current goal is
PNoEqLe_tra beta gamma Hb Hc p q r L1 H2.
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