pub const EIGHT_TORSION: [EdwardsPoint; 8]
The 8-torsion subgroup \(\mathcal E \).
In the case of Curve25519, it is cyclic; the \(i\)-th element of the array is \([i]P\), where \(P\) is a point of order \(8\) generating \(\mathcal E\).
Thus \(\mathcal E\) is the points indexed by
\(\mathcal E\) is the points indexed by