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Friday the 13th occurs when the thirteenth day of a month falls on Friday, which
superstition holds to be a day of good or bad
luck. In the
Gregorian calendar, this day occurs at least once, but at most three times a year. Any month's 13th day will fall on a Friday if the month starts on a Sunday. In
2009 this applies to the months of
February,
March, and
November. The next instance of this appears on the calendar for the year
2015.
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