Top panels: 2PCF measurements for four comoving snapshots from the Flagship I simulation of the Model 3 HOD. Bottom panels: Same but for the 3PCF measurements. The triangular configurations are ordered by increasing values of r₁₂, r₁₃, and r₂₃ under the condition r₁₂ ≤ r₁₃ ≤ r₂₃, as depicted in Fig. A.1. The circles are colour-coded according to the η, while the vertical grey lines mark a group of triangles that share the same value of the smaller side (r₁₂).