Let x and y be given.
Assume Hx Hy.
Assume H1.
Apply H1 to the current goal.
Assume H1.
Apply or3I1 to the current goal.
An exact proof term for the current goal is H1.
Assume H1.
Apply H1 to the current goal.
Apply or3I2 to the current goal.
An
exact proof term for the current goal is
SNo_eq x y Hx Hy H2 H3.
Assume H1.
Apply or3I3 to the current goal.
An exact proof term for the current goal is H1.
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