This file is indexed.

/usr/share/doc/cron/README.anacron is in cron 3.0pl1-128ubuntu2.

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
12
13
14
To ease coordination with anacron, the invocation of the run-parts for
the /etc/cron.daily, /etc/cron.weekly, and /etc/cron.monthly directories
was changed to the form

         test -e /usr/sbin/anacron || run-parts --report /etc/cron.daily

What this means is that if anacron has been installed, it will
be responsible for running those scripts. This is the standard
configuration of anacron: if you simply install both cron and anacron,
things will work as expected.

However, if you have modified your anacron configuration
(/etc/anacrontab), you may need to re-adjust it in order to accommodate
this change.