Can you find the unique theme for each row and each column in the Tic-Tac-Toe board below?
Examples of acceptable answers would be:
Numbers whose digits add up to 18.
Numbers which are cubes.
Numbers whose digits are in ascending order.
Numbers which are divisible by seven.
Examples of answers which will not be accepted are:
Numbers which are less than 60,000.
Numbers which are divisible by one.
Numbers which are positive.
These answers are too general and they are not unique (they work for more than one row or column).
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Solution to the Problem:
Top row: Fibonacci Numbers
1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765, ...
Middle row: Factors of 60 (also Wythoff Array):
1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60
Bottom row: Numbers which are palindromes:
11, 22, 101, 282, 1551, 473374,
First column: Prime numbers
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97,
101, ... 181, ... 233, ...
Second column: Multiples of Five:
5, 10, 15, 20, 25, 30, 35, 40, ... 505, ... 6765, ...
Third column: Even numbers:
0, 2, 4, 6, 8, 10, 12, 14, 16, ...
Correctly solved by:
| 1. Anonymous | ----------- |
| 2. Colin (Yowie) Bowey | Beechworth, Victoria, Australia |
| 3. Veena Mg | Bangalore, Karnataka, India |
| 4. Kelly Stubblefield | Mobile, Alabama |