A116386 Number of calendar weeks in the year n (starting at n=0 for the year 2000).

54, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 54, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 54, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53

Offset: 0

Author

Sergio Pimentel, Mar 15 2006

Keywords

• nonn
• easy

Comments

Since 365/7 = 52.14 > 52, every year has at least 53 weeks (although the first and / or the last calendar weeks might not be complete and belong to two different years). Only if a leap year begins in a Saturday (the last day of the calendar week), a year can have 54 different calendar weeks (being the first and last of only one day). Years with 54 calendar weeks are: 2000, 2028, 2056, 2084, 2124, 2152, etc. It happens 13 times in a 400 year cycle.

Examples

			E.g. a(0)=54 because the year 2000 had 54 calendar weeks (since Jan 01 2000 was a Saturday and Dec 31 2000 was a Sunday)
		

Links

• Index entries for sequences related to calendars

Crossrefs

Cf. A060512, A061251, A003786, A090651, A101312.