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| <math>n^2 - n + 17</math> || 2 || all numbers 1-16, because 17 is one of the [[lucky numbers of Euler]]. || 2 | | <math>n^2 - n + 17</math> || 2 || all numbers 1-16, because 17 is one of the [[lucky numbers of Euler]]. || 2 | ||
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==Multiples== | |||
===Interesting multiples=== | |||
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! Number !! Prime factorization !! What's interesting about it | |||
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| [[1729]] || [[7]] times [[13]] times [[19]] || third [[Carmichael number]], i.e., absolute pseudoprime<br>Smallest number expressible as a sum of two positive cubes in two different ways. | |||
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Latest revision as of 22:06, 15 January 2012
This article is about a particular natural number.|View all articles on particular natural numbers
Summary
Factorization
The number 19 is a prime number.
Prime-generating polynomials
Below are some polynomials that give prime numbers for small input values, which give the value 19 for suitable input choice.
| Polynomial | Degree | Some values for which it generates primes | Input value at which it generates 19 |
|---|---|---|---|
| 2 | all numbers 1-16, because 17 is one of the lucky numbers of Euler. | 2 |
Multiples
Interesting multiples
| Number | Prime factorization | What's interesting about it |
|---|---|---|
| 1729 | 7 times 13 times 19 | third Carmichael number, i.e., absolute pseudoprime Smallest number expressible as a sum of two positive cubes in two different ways. |