question about the data

[Potato-Huang]

1. P3，“……For datasets containing k different annotations for the same image we use a different approach: for each set of 1 + k images (input plus k annotations), we randomly select m elements, where m ≤ n + 1 ≤ 16. These m-tuples are then concatenated to form visual sequences”. What is 'n' here?
2. The ratio of colorization and mask about ImageNet can be randomly set？