an argument n for the weekday instances,
which will signify the nth occurrence of this weekday in the period. For example, with MONTHLY, or with YEARLY and
BYMONTH, using FR(+1) in byweekday will specify the first friday of the month where the recurrence happens. Notice
that in the RFC documentation, this is specified as BYDAY, but was renamed to avoid the ambiguity of that keyword.
</p></div></div>
    </li><li name="org.saddle.time.RRule#byWeekNo" visbl="pub" data-isabs="false" fullComment="yes" group="Un