Let alpha, beta, p and q be given.
Assume Ha Hb.
rewrite the current goal using
SNoLev_PSNo alpha Ha p (from left to right).
We will
prove PNoEq_ alpha (λgamma ⇒ gamma ∈ PSNo alpha p) p.
An exact proof term for the current goal is Ha.
An exact proof term for the current goal is H1.
An exact proof term for the current goal is Hb.
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