Man pages matching name r in section 1:

R.1.en	debian 10 / r-base-core
r.1.en	debian 10 / r-cran-littler
R.1.en	debian 11 / r-base-core
r.1.en	debian 11 / r-cran-littler
R.1.en	debian 12 / r-base-core
r.1.en	debian 12 / r-cran-littler