class A{static void Main(){for(var e=53;;e--){var s="ABCDEFGHIJKLMNOPQRSTUVWXYZ".Substring(0,e/2);System.Console.WriteLine(e%2==0?s.Replace((char)('@'+e/2),(char)('`'+e/2)):s);}}}
Note that non-ascii characters in the above source code will be escaped (such as \x9f).