The mathematician Johann Friederich Carl Gauss proposed a method for determining Easter dates, the rules of which were set out in the Council of Nicaea (325 AD).
As defined, Easter should be celebrated on the Sunday following the first full moon of spring (in Europe). Gauss developed a rule of thumb for calculating the date of Easter in the Gregorian calendar from 1583.
Consider THE as the year, and m and no two numbers that vary over time according to the following table:
|1583-1699||m = 22, n = 2|
|1700-1799||m = 23, n = 3|
|1800-1899||m = 23, n = 4|
|1900-2099||m = 24, n = 5|
|2100-2199||m = 24, n = 6|
The the rest of the division of A by 19
B the rest of the division of A by 4
ç the rest of the division of A by 7
d rest of the division of 19a + m by 30
and the rest of the division 2b + 4c + 6d + n by 7
So Easter will be on 22 + d + e March or d + e-9 April
1. April 26 should always be replaced by April 19.
2. April 25 should be replaced by April 18 if d = 28, e = 6, and a> 10.
Do you want to know how Gauss came to this conclusion? We would also like to know :-)