Kurt Richter

1. As always, pay attention to the kind of keypad in front of you. You get both letters and numbers with this one.

2. Let's think of numbers as words for a moment.

3. And now think of them as numbers again—but this time, the numbers you get by typing their names out on this keypad.

4. What could a number's inner self be?

5. Try seeing what keys you would hit if you were to type any of the keypad numbers in letters: ONE, TWO, etc. What do you notice?

6. For only three numbers do you need the key of that number to type it. THREE is 84733 for example.

7. The other two are 7 (SEVEN = 73836) and EIGHT (34448).

(SOLUTION FOLLOWS)

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8. So the numbers that don't qualify must be 1 2 4 5 6 9.