source 2013 Oliveira--López--Aranha--Rodríguez-Henríquez "Lambda coordinates for binary elliptic curves"; database entry contributed by Chitchanok Chuengsatiansup compute A = Z1^2 compute B = L1^2 compute C = L1 Z1 compute D = a2 A compute E = B + C + D compute F = X1 Z1 compute X3 = E^2 compute Z3 = E A compute L3 = F^2 + X3 + E C + Z3