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%I #4 Nov 02 2013 23:40:30
%S 0,1,3,6,8,9,11,14,15,17,18,19,20,22,23,26,27,28,29,31,32,34,35,37,38,
%T 40,41,43,45,46,49,52,54,55,57,58,60,61,63,64,66,68,69,71,72,73,74,75,
%U 77,78,80,81,83,86,87,89,91,92,94,95,98,100,101,103,104,106,109,110,112
%N Number of months after which a date can fall on the same day of the week, in the Julian calendar.
%C In the Julian calendar, a year is a leap year if and only if it is a multiple of 4 and all century years are leap years.
%C Assuming this fact, this sequence is periodic with a period of 336.
%H Time And Date, <a href="http://www.timeanddate.com/calendar/repeating-month.html">Repeating Months</a>
%H Time And Date, <a href="http://www.timeanddate.com/calendar/julian-calendar.html">Julian Calendar</a>
%o (PARI) m=[0,3,3,6,1,4,6,2,5,0,3,5];n=[31,28,31,30,31,30,31,31,30,31,30,31];y=vector(336,i,(m[((i-1)%12)+1]+((5*((i-1)\48)+(((i-1)\12)%4)-!((i-1)%48)-!((i-2)%48))))%7);x=vector(336,i,n[((i-1)%12)+1]+!((i-2)%48));for(p=0,336,for(q=0,336,if(y[(q%336)+1]==y[((q+p)%336)+1],print1(p", ");break)))
%Y Cf. A230995-A231014.
%Y Cf. A231005 (Gregorian calendar).
%K nonn,easy
%O 0,3
%A _Aswini Vaidyanathan_, Nov 02 2013
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