I’m already tired of seeing this all over Facebook, Twitter, etc.
This October (2010) has 5 Fridays, 5 Saturdays, and 5 Sundays all in one month. It happens only once in 823 years.
This does not only happen once every 823 years. One only has to go back to 2004 to see an October with 5 Fridays, 5 Saturdays, and 5 Sundays.
10/1/10
10/1/21
10/1/27
10/1/32
10/1/38
10/1/49
10/1/55
10/1/60
10/1/66
10/1/77
10/1/83
10/1/88
10/1/94
10/1/00
Next 100 years worth, using a mumps routine
faut: en 1909,1915,1920,1926,1937,1943,1948,1954,1965,1971,1976,1982,1993,1999,2004,2010,
2021, 2027, 2032,….
à chaque fois que le 1er octobre tombe un vendredi forcément