see "long years 2000-2099: " for year = 2000 to 2100 num1 = (year-1900)%7 num2 = floor((year-1904)/4) num3 = (num1+num2+5)%7 if num3 = 0 or (num1 = 6 and num3 = 1) see "" + year + " " ok next