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%I #4 Nov 02 2013 23:38:37
%S 1,2,3,4,8,9,10,13,14,15,16,19,20,21,24,25,26,27,30,31,32,36,37,38,41,
%T 42,43,44,47,48,49,52,53,54,55,58,59,60,64,65,66,69,70,71,72,75,76,77,
%U 80,81,82,83,86,87,88,92,93,94,97,98,99,100,103,104,105,109,110,111
%N Number of years after which it is not possible to have a date falling on the same day of the week, in the Gregorian calendar.
%C In the Gregorian calendar, a non-century year is a leap year if and only if it is a multiple of 4 and a century year is a leap year if and only if it is a multiple of 400.
%C Assuming this fact, this sequence is periodic with a period of 400.
%C This is the complement of A230995.
%H Time And Date, <a href="http://www.timeanddate.com/calendar/repeating.html">Repeating Calendar</a>
%H Time And Date, <a href="http://www.timeanddate.com/calendar/gregorian-calendar.html">Gregorian Calendar</a>
%o (PARI) for(i=0,400,j=0;for(y=0,400,if(((5*(y\4)+(y%4)-(y\100)+(y\400))%7)==((5*((y+i)\4)+((y+i)%4)-((y+i)\100)+((y+i)\400))%7),j=1));if(j==0,print1(i", ")))
%Y Cf. A230995-A231014.
%Y Cf. A231003 (Julian calendar).
%K nonn,easy
%O 1,2
%A _Aswini Vaidyanathan_, Nov 02 2013
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