Let x0 of type ι be given.

Let x1 of type ι → ι → ι be given.

Let x2 of type ι → ι → ο be given.

Let x3 of type ι be given.

Let x4 of type ι be given.

Apply pack_b_r_e_e_4_eq with pack_b_r_e_e x0 x1 x2 x3 x4, x0, x1, x2, x3, x4.

Let x5 of type ι → ι → ο be given.

Assume H0: x5 (pack_b_r_e_e x0 x1 x2 x3 x4) (pack_b_r_e_e x0 x1 x2 x3 x4).

The subproof is completed by applying H0.

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Proofgold Proof