How do you get the date for Easter of a given year?

REM "This formula returns the date of Easter day for the year of a given date D";
REM "Is valid until year 4000";
REM "Contributed from billingt@online.no";

D:=[30.07.97];
Year:=@Year(D);

c:=@Integer(Year/100);
n:=Year-19*@Integer(Year/19);
k:=@Integer((c-17)/25);
i:=c-@Integer(c/4)- @Integer((c-k)/3)+19*n+15;
ii:=i-30*@Integer(i/30);
iii:=ii-@Integer(ii/28)*(1-@Integer(ii/28)*@Integer(29/(ii+1))*@Integer((21-n)/11));

j:=Year+@Integer(Year/4)+iii+2-c+@Integer(c/4);
jj:=j-7*@Integer(j/7);
l:=iii-jj;
EasterMonth:=3+@Integer((l+40)/44);
EasterDay:=l+28-31*@Integer(EasterMonth/4);
@Date(Year;EasterMonth;EasterDay);

Applies to Notes Versions: 3 4 4.5 4.6 5