Let x and y be given.

Assume Hx: SNo x.

Assume Hy: SNo y.

Apply add_SNo_prop1 x y Hx Hy to the current goal.

Assume H.

Apply H to the current goal.

Assume H.

Apply H to the current goal.

Assume H.

Apply H to the current goal.

Assume H.

Apply H to the current goal.

Assume H _ _ _ _ _.

An exact proof term for the current goal is H.

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