Lah numbers: Difference between revisions
Content added Content deleted
| Line 478: | Line 478: | ||
| k > n = 0 |
| k > n = 0 |
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| k < 1 || n < 1 = 0 |
| k < 1 || n < 1 = 0 |
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| otherwise = (factorial n * factorial (pred n)) |
| otherwise = (factorial n * factorial (pred n)) `div` |
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`div` |
(factorial k * factorial (pred k)) `div` |
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(factorial k * factorial (pred k)) |
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`div` |
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factorial (n - k) |
factorial (n - k) |
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