We prove the intermediate claim Li0: OSNo i0.
An exact proof term for the current goal is OSNo_Octonion_i0.
We prove the intermediate claim Li4: OSNo i4.
An exact proof term for the current goal is OSNo_Quaternion_k.
We prove the intermediate claim Li5: OSNo i5.
An exact proof term for the current goal is OSNo_Octonion_i5.
We prove the intermediate claim Li4i0: OSNo (i4 ⨯ i0).
An exact proof term for the current goal is OSNo_mul_OSNo i4 i0 ?? ??.
Apply OSNo_proj0proj1_split (i4 ⨯ i0) (:-: i5) ?? (OSNo_minus_OSNo i5 ??) to the current goal.
rewrite the current goal using minus_OSNo_proj0 i5 ?? (from left to right).
rewrite the current goal using OSNo_p0_i5 (from left to right).
rewrite the current goal using mul_OSNo_proj0 i4 i0 ?? ?? (from left to right).
rewrite the current goal using OSNo_p0_i0 (from left to right).
rewrite the current goal using OSNo_p1_i0 (from left to right).
rewrite the current goal using OSNo_p0_k (from left to right).
rewrite the current goal using OSNo_p1_k (from left to right).
We will prove k * 0 + - (1 ' * 0) = - 0.
rewrite the current goal using mul_HSNo_0R k HSNo_Quaternion_k (from left to right).
rewrite the current goal using mul_HSNo_0R (1 ') (HSNo_conj_HSNo 1 HSNo_1) (from left to right).
rewrite the current goal using minus_HSNo_0 (from left to right).
An exact proof term for the current goal is add_HSNo_0L 0 HSNo_0.
rewrite the current goal using minus_OSNo_proj1 i5 ?? (from left to right).
rewrite the current goal using OSNo_p1_i5 (from left to right).
rewrite the current goal using mul_OSNo_proj1 i4 i0 ?? ?? (from left to right).
rewrite the current goal using OSNo_p0_i0 (from left to right).
rewrite the current goal using OSNo_p1_i0 (from left to right).
rewrite the current goal using OSNo_p0_k (from left to right).
rewrite the current goal using OSNo_p1_k (from left to right).
We will prove 1 * k + 0 * 0 ' = - (- k).
rewrite the current goal using conj_HSNo_id_SNo 0 SNo_0 (from left to right).
rewrite the current goal using mul_HSNo_0L 0 HSNo_0 (from left to right).
rewrite the current goal using mul_HSNo_1L k HSNo_Quaternion_k (from left to right).
rewrite the current goal using minus_HSNo_invol k HSNo_Quaternion_k (from left to right).
An exact proof term for the current goal is add_HSNo_0R k HSNo_Quaternion_k.
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