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Tests currently running
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| Property | Definition |
Example
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| Multiple of 3 | Each digit in the number is a multiple of three (remember 3 * 0 = 0!). | |
| Power of 2 | Each digit in the number is a power of two (remember 20=1!). | |
| Consecutive digits | A number has n consecutive digits when it contains n consecutive integers, regardless of order. | |
| Vampire numbers | A number is a vampire number if there exists a factorization of it using only the digits of the original number. The factorization is called the "fangs" of the original number. | |
| Prime numbers | The number can only be divided by itself and one. Dividing by any other number causes a remainder. There are exactly 5,761,455 prime numbers under 100 million. | |
| Palindrome | The numbers digits are symmetric so that the first and last digits are the same, the second and second-to-last digits are the same, etc. This property occurs in 0.010% of 8-digit numbers. | |
| Even/Odd | If a number has all odd digits or all even digits, the property is noted. This occurs in 0.39% of 8-digits numbers. | |
| Sum of digits | If the sum of the digits is less than 25 or greater than 47, then this property is noted. | |
| Fibonacci sequence | A number in the Fibonacci sequence is the sum of the two previous numbers in that sequence. The first two are 1 and 1, so the next number would be 2, followed by 3, then 5, and so on. | |
| Unique digits | When a particular digit only appears once, that is a unique digits. If there are less than three or more than six unique digits, this property is activated. | |
| Forward runs | When consecutive digits are consecutive increasing integers (for runs longer than two), then this property is activated. | |
| Backward runs | When consecutive digits are consecutive decreasing integers (for runs longer than two), then this property is activated. | |
| Factorial | The factorial of n is the product of: n*(n-1)*(n-2) *... * (n - (n -2)) * 1 |
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| Tuples together | A tuple is a pair, triple, 4-of-a-kind, etc. When the unordered number has a repeated digit, it has a tuple together. | |
| Tuples | When the ordered (or sorted) number has a repeated digit, the unordered number has a tuple apart. In other words, this is a tuple "together or apart". | |
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