Names of the days of the week is followed by a number indicating the day: "Monday" is literally "star day one", "Tuesday" is "star day two", etc. The exception is Sunday, where rì (日), meaning "sun" or "day", is used instead of a number. In Swahili, the day begins at sunrise, unlike in the Arabic and Hebrew calendars where the day starts at sunset (therefore an offset of twelve hours), and unlike in the Western world where the day starts at midnight (therefore an offset of six hours). Saturday is therefore the first day of the week, as it is the day that includes the first night
Determination of the day of the week where is the day of the week (counting upwards from 1 on Sunday instead of 0 in Gauss's version); and , , and are numbers depending on the day, month, century and year which are tabulated in the "Complete table: Julian and Gregorian calendars" above. Note that the numbers tabulated for y can also be described by the following equation: Where So, for example, if you want to find 'y' for the year 1987: In Zeller’s algorithm, the months are numbered from 3 for March to 14 for February. The year is assumed to begin in March; this means, for