In a calendar year, how many months, maximum, can start on a Sunday? What will be the next (very unlucky?) year when this maximum occurs?
Must every calendar year have at least one month that starts on a Sunday?
1) Papal note: Pope Gregory,
when formulating our current (Gregorian) calendar, studied this exact
same question. However, he was interested in the question of
months which would include Friday the 13th. As Richard seems to
be aware, any month which begins with a Sunday is unlucky in that it
includes Friday the 13th.
2) Papal Question: Before
finishing the calendar, Pope Gregory also investigated and determined
the following question. The cycle of month lengths and starting
days eventually must repeat (recycle?). How long is the cycle,
and do some starting days occur more frequently than
others? If so, which day or days are most likely to start a
month?
Papal question
