Estimates of RU counts using recruited reads. (A) (k₁, k₂, k₃) = (1,3,1); RU count ≥5. (B) (k₁, k₂, k₃) = (0,3,1); RU count ≥4. (C) (k₁, k₂, k₃) = (0,3,0); RU count = 3.