/usr/lib/R/site-library/pillar/INDEX is in r-cran-pillar 1.0.1-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11  | colonnade               Format multiple vectors in a tabular display
dim_desc                Format dimensions
expect_known_display    Test helpers
extra_cols              Retrieve information about columns that didn't
                        fit the available width
get_extent              Calculate display width
new_ornament            Helper to define the contents of a pillar
new_pillar_shaft        Constructor for column data
pillar                  Format a vector suitable for tabular display
pillar_shaft            Column data
style_num               Styling helpers
 |