PERPETUAL CALENDAR FOR THE GREGORIAN CALENDAR

摘要

A perpetual calendar that determines the day of any Gregorian calendar date that is in Anno Domini. This one-page perpetual calendar has five main tables: Days of the Week, Months, Days of the Month, Years and Leap Years. The Days of the Week contains days (Sunday to Saturday) and numbers (0, 1,...,6). The Days of the Week repeats twice here. The Months contains January to December. The Days of the Month contains whole numbers (1 to 31). The years (a table with tables) has four tables: Thousands' Place, Hundreds' Place, Tens' Place and Ones' Place. The Thousands' Place contains numbers (1000, 2000, ..., 9000). The Hundreds' Place contains numbers (100, 200, ..., 900). The Tens' Place contains numbers (10, 20, ..., 90). The Ones' Place contains whole numbers (1 to 9). The Leap Years (a table with tables) has three tables: Leap Years Before a Centennial, Centennials and Millenniums. The Leap Years Before a Centennial contains numbers (4, 8, ..., 96). The Centennials contains numbers (100, 200, ..., 900). The Millenniums contains numbers (1000, 2000, ..., 9000). Methods that adhere to both the Gregorian Calendar and the Fortunado's algorithm (an algorithm for knowing the day of any Gregorian calendar date that is in Anno Domini) are used to determine which row and column the contents are placed. Modifications will be made to make a calendar for each year. Modifications will be made to know the day of any Gregorian calendar date later than 9999 Anno Domini.