Leap year starting on Friday

A leap year starting on Friday is any year with 366 days (i.e. it includes 29 February) that begins on Friday 1 January and ends on Saturday 31 December. Its dominical letters hence are CB. The most recent year of such kind was 2016 and the next one will be 2044 in the Gregorian calendar^[1] or, likewise, 2000 and 2028 in the obsolete Julian calendar.

Any leap year that starts on Friday has only one Friday the 13th: the only one in this leap year occurs in May.

From August of the common year preceding this year to October in this type of year is the longest period that occurs without a Lucky Monday, in other words the 3rd day of the month being on a Monday (14 months).

In this type of year, all dates (except 29 February) fall on their respective weekdays the maximal 58 times in the 400 year Gregorian calendar cycle. Leap years starting on Sunday share this characteristic.

^ Robert van Gent (2017). "The Mathematics of the ISO 8601 Calendar". Utrecht University, Department of Mathematics. Retrieved 20 July 2017.

[math-1] Robert van Gent (2017). "The Mathematics of the ISO 8601 Calendar". Utrecht University, Department of Mathematics. Retrieved 20 July 2017.

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