pub fn supersingular_graph(p: &BigInt) -> Option<Vec<SsVertex>>Expand description
Build the supersingular ℓ=2 isogeny graph over 𝔽_{p²} (requires p ≡ 3 (mod 4)). Breadth-first
from the supersingular vertex j = 1728, following the roots of Φ₂(j,·). Because the graph is
connected, this reaches every supersingular j-invariant; its size is the supersingular mass
⌊p/12⌋ + ε and every vertex has out-degree 3. None if p ≢ 3 (mod 4).