We prove the intermediate claim Li1: OSNo i1.
An exact proof term for the current goal is OSNo_Complex_i.
We prove the intermediate claim Li2: OSNo i2.
An exact proof term for the current goal is OSNo_Quaternion_j.
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 Li2i1: OSNo (i2 ⨯ i1).
An exact proof term for the current goal is OSNo_mul_OSNo i2 i1 ?? ??.
Apply OSNo_proj0proj1_split (i2 ⨯ i1) (:-: i4) ?? (OSNo_minus_OSNo i4 ??) to the current goal.
rewrite the current goal using minus_OSNo_proj0 i4 ?? (from left to right).
rewrite the current goal using OSNo_p0_k (from left to right).
rewrite the current goal using mul_OSNo_proj0 i2 i1 ?? ?? (from left to right).
rewrite the current goal using OSNo_p0_i (from left to right).
rewrite the current goal using OSNo_p1_i (from left to right).
rewrite the current goal using OSNo_p0_j (from left to right).
rewrite the current goal using OSNo_p1_j (from left to right).
We will prove j * i + - (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_0R 0 HSNo_0 (from left to right).
rewrite the current goal using minus_HSNo_0 (from left to right).
rewrite the current goal using add_HSNo_0R (j * i) (HSNo_mul_HSNo j i HSNo_Quaternion_j HSNo_Complex_i) (from left to right).
An exact proof term for the current goal is Quaternion_j_i.
rewrite the current goal using minus_OSNo_proj1 i4 ?? (from left to right).
rewrite the current goal using OSNo_p1_k (from left to right).
rewrite the current goal using mul_OSNo_proj1 i2 i1 ?? ?? (from left to right).
rewrite the current goal using OSNo_p0_i (from left to right).
rewrite the current goal using OSNo_p1_i (from left to right).
rewrite the current goal using OSNo_p0_j (from left to right).
rewrite the current goal using OSNo_p1_j (from left to right).
We will prove 0 * j + 0 * i ' = - 0.
rewrite the current goal using mul_HSNo_0L (i ') (HSNo_conj_HSNo i HSNo_Complex_i) (from left to right).
rewrite the current goal using mul_HSNo_0L j HSNo_Quaternion_j (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.
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