Problem Statement |
| | A number is preprime if it has exactly 4 positive integer divisors. For example, 6 is preprime because its divisors are 1, 2, 3, and 6. The integers 6, 8, 10, 14 form the beginning of an infinite sequence of preprime numbers. Find the n-th element of this sequence, where n is a 1-based index. |
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Definition |
| | | Class: | PreprimeNumbers | | Method: | nthNumber | | Parameters: | int | | Returns: | int | | Method signature: | int nthNumber(int n) | | (be sure your method is public) |
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Constraints |
| - | n will be between 1 and 1000000, inclusive. |
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Examples |
| 0) | |
| | | Returns: 8 | | The beginning of an infinite sequence of preprime numbers is: 6, 8, 10, 14, ... The second number is 8. |
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| 1) | |
| | | Returns: 14 | | The beginning of an infinite sequence of preprime numbers is: 6, 8, 10, 14, ... The fourth number is 14. |
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| 2) | |
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| 3) | |
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