ARISTEAN DAY NUMBER or ADN

DETERMINING THE DAY OF THE WEEK
OF AN ARISTEAN DAY NUMBER^©

Aristeo Canlas Fernando, Peace Crusader

A date in the Aristean calendar is assigned an Aristean Day Number or ADN. The ADN is the number of days of the date from the beginning of the year, i.e. January 1. The ADN is the same every year for dates on or before June 30 whether the year is a common year or a leap year. The ADN of June 30 is 182.

The leap year rule of the Aristean calendar is the same as that of the Gregorian calendar, i.e. the year is a leap year if it is divisible by four except if it is a century year and is not divisible by 400.

During common year when there are 365 days in a year, July 1 is day number 183 and December 31 is day number 365. However, during leap year, there are 366 days in a year. June 31 is Leap Year Day and its ADN is 183. Hence, July 1 is day number 184 and December 31 is day number 366.

COMMON YEAR

A common or ordinary year has 365 days. The last date of the year is December 31 and its ADN is 365. This date is a no-week day. The date is called World Peace Day, and to the religious, Grand Sabbath.

Steps to determine the day of the week of an ADN in a common year :

Divide the ADN by 7.
Get the remainder.
The remainder determines the day of the week based on the following:

Remainder Day of Week

1 Monday

2 Tuesday

3 Wednesday

4 Thursday

5 Friday

6 Saturday

0 Sunday

N.B. The quotient does not only help us determine day of the week of the ADN but also tells its week number. The whole number determines the week number. If the remainder is 1, 2, 3, 4, 5, or 6, add 1 to the whole number and that will be the week number. If the remainder is 0, the whole number is the week number.

Examples:

ADN is 255. 255 divided by 7 equals 36, remainder 3. The day number, therefore, is a Wednesday. The week number is 37, i.e. 36 + 1.
ADN is 133. 133 divided by 7 equals 19, remainder 0. The day number, therefore, is a Sunday. The week number is 19.

LEAP YEAR

A leap year has 366 days. The last date of the year is December 31 and its ADN is 366. This date is a no-week day. The date is called World Peace Day, and to the religious, Grand Sabbath. Leap Year Day is on June 31 and its ADN is 183. The date is also a no-week day. The date is simply called Leap Year Day, or Leap Day, and to the religious, Glorious Sabbath.

Steps to determine the day of the week of an ADN in a leap year and the ADN is less than 183:

1. Divide the ADN by 7.

2. Get the remainder.

3. The remainder determines the day of the week as shown above in common year. The whole number determines the week number as noted above also.

Examples:

1. ADN is 125. 125 divided by 7 equals 17, remainder 6. The day number, therefore, is a Saturday. The week number is 18, i.e. 17 + 1.

2. ADN is 77. 77 divided by 7 equals 11, remainder 0. The day number, therefore, is a Sunday. The week number is 11.

Steps to determine the day of the week of an ADN in a leap year and the ADN is more than 183:

1. Subtract 1 from ADN to get the difference.

2. Divide the difference by 7.

3. Get the remainder.

4. The remainder determines the day of the week as shown above in common year. The whole number determines the week number as noted above also.

Examples:

1. ADN is 265. Subtract 1 from 265 equals 264. 264 divided by 7 equals 37, remainder 5. The day number, therefore, is a Friday. The week number is 38, i.e. 37 + 1.

2. ADN is 323. Subtract 1 from 323 equals 322. 322 divided by 7 equals 46, remainder 0. The day number, therefore, is a Sunday. The week number is 46.

Text Box: Technically, during leap year, July 1 is day number 184 and December 31 is day number 366. Since a date’s day of the week is the same whether the year is a common year or a leap year, for ease of calculation, June 31 could be assumed to be day number 366, and July 1 would remain to be day number 183. The determination of the day of the week is therefore simplified.

File: dayofweek.htm – Last updated: 2005 November 12