Determination of the day of the week *104804 + 4, "n" = 104804 and "k" = 4 which implies that August 13, 2009 is the fourth day into the 104805th week since 01/01/0001. 13 August 2009 is Thursday; therefore, the first day of the week must be Monday, and it is concluded that the first day 01/01/0001 of the calendar is "Monday". Based on this, the remainder of the ratio "Base/7", defined above as "k", decides what day of the week it is. If "k" = 0, it's Monday, "k" = 1, it's Tuesday, etc. Determination of the day of the week The determination of the day
Determination of the day of the week example, that January 1995 is to be treated as month 13 of 1994. The formula for the Gregorian calendar is where The only difference is one between Zeller’s algorithm () and the Gaussian algorithm (), that is . So we can get the values of months from those for the Gaussian algorithm by adding one: In a partly tabular method by Schwerdtfeger, the year is split into the century and the two digit year within the century. The approach depends on the month. For , so is between 0 and 99. For , The formula for the day of the