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| <math>n^2 - n + 11</math> || 2 || all numbers 1-10, because 11 is one of the [[lucky numbers of Euler]]. || 2 | | <math>n^2 - n + 11</math> || 2 || all numbers 1-10, because 11 is one of the [[lucky numbers of Euler]]. || 2 | ||
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==Multiples== | |||
===Interesting multiples=== | |||
{| class="sortable" border="1" | |||
! Number !! Prime factorization !! What's interesting about it | |||
|- | |||
| [[1105]] || [[5]] times [[13]] times [[17]] || second [[Carmichael number]], i.e., absolute pseudoprime | |||
|- | |||
| [[1729]] || [[7]] times [[13]] times [[19]] || third [[Carmichael number]], i.e., absolute pseudoprime | |||
|- | |||
| [[2821]] || [[7]] times [[13]] times [[31]] || fifth [[Carmichael number]], i.e., absolute pseudoprime | |||
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Revision as of 22:02, 15 January 2012
This article is about a particular natural number.|View all articles on particular natural numbers
Summary
Factorization
The number 13 is a prime number.
Prime-generating polynomials
Below are some polynomials that give prime numbers for small input values, which give the value 13 for suitable input choice.
| Polynomial | Degree | Some values for which it generates primes | Input value at which it generates 13 |
|---|---|---|---|
| 2 | all numbers 1-10, because 11 is one of the lucky numbers of Euler. | 2 |
Multiples
Interesting multiples
| Number | Prime factorization | What's interesting about it |
|---|---|---|
| 1105 | 5 times 13 times 17 | second Carmichael number, i.e., absolute pseudoprime |
| 1729 | 7 times 13 times 19 | third Carmichael number, i.e., absolute pseudoprime |
| 2821 | 7 times 13 times 31 | fifth Carmichael number, i.e., absolute pseudoprime |