Henry Ernest Dudeney/Puzzles and Curious Problems/278 - The Thirty-Six Letter Puzzle

by : $278$

 * The Thirty-Six Letter Puzzle
 * If you try to fill up this square by repeating the letters $A$, $B$, $C$, $D$, $E$, $F$,
 * ''so that no $A$ shall be in a line across, downwards, or diagonally, with another $A$,
 * no $B$ with another $B$, no $C$ with another $C$, and so on,
 * you will find that it is impossible to get in all the $36$ letters under these conditions.


 * Dudeney-Puzzles-and-Curious-Problems-278.png


 * The puzzle is to place as many letters as possible.