Multigrid inpainting schedule for an N_side = 128 map. Filled nodes represent successive iterations of diffusion steps (Eq. (A.17)), downward strokes represent calculation of the residual (Eq. (A.19)) and its downgrade to the coarser grid, while upward strokes represent the upgrade of the correction (Eq. (A.20)) to the finer grid, and solid arrows represent the merge of the correction into the solution (Eq. (A.21)). Eight diffusion steps are used at all grid levels except the lowest, where 64 steps are used, which is enough to find the static solution there.