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%I
%S 1587,1598,1609,1615,1626,1637,1643,1654,1665,1671,1682,1693,1699,
%T 1705,1711,1722,1733,1739,1750,1761,1767,1778,1789,1795,1801,1807,
%U 1818,1829,1835,1846,1857,1863,1874,1885,1891,1903,1914,1925,1931,1942,1953,1959,1970,1981,1987,1998
%N Non-leap years beginning and ending on Thursday.
%C Gregorian calendar repeats after every 400 years because number of days in 400 years is 146097 which is a multiple of 7.
%C Non-century years are leap years if and only if they are multiples of 4 while century years are leap years if and only if they are multiples of 400.
%C 44 occurrences in 400 years.
%C Months having Friday the 13th: February, March and November.
%C 365 day ordinary year: 52 Sundays, 52 Mondays, 52 Tuesdays, 52 Wednesdays, 53 Thursdays, 52 Fridays, 52 Saturdays.
%H Time and Date, <a href="http://www.timeanddate.com/calendar/gregorian-calendar.html">The Gregorian calendar</a>
%H Time and Date, <a href="http://www.timeanddate.com/calendar/?year=2009">2009</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Gregorian_calendar">Gregorian calendar</a>
%t Select[Range[1583, 2600], DayOfWeek[{#, 1, 1}, Calendar -> Gregorian] == Thursday && DaysBetween[{#, 1, 1}, {# + 1, 1, 1}, Calendar -> Gregorian] == 365 &, 50] (* _T. D. Noe_, Apr 22 2013 *)
%t Select[Range[1583,2600],!LeapYearQ[{#}]&&DayName[{#,1,1}]==DayName[ {#,12,31}] == Thursday&] (* _Harvey P. Dale_, May 06 2022 *)
%K nonn
%O 1,1
%A _Aswini Vaidyanathan_, Apr 21 2013
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