Pauli group

In physics and mathematics, the Pauli group ${\displaystyle G_{1}}$ on 1 qubit is the 16-element matrix group consisting of the 2 × 2 identity matrix ${\displaystyle I}$ and all of the Pauli matrices

together with the products of these matrices with the factors ${\displaystyle -1}$ and ${\displaystyle \pm i}$:

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