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The number 13 is a [[satisfies property::prime number]]. | The number 13 is a [[satisfies property::prime number]]. | ||
==Prime-generating polynomials== | ===Properties and families=== | ||
{| class="sortable" border="1" | |||
! Property or family !! Parameter values !! First few numbers !! Proof of satisfaction/membership/containment | |||
|- | |||
| [[satisfies property::prime number]] || it is the 6th prime number || {{#lst:prime number|list}} || divide and check | |||
|- | |||
| [[satisfies property::Proth prime]]: prime of the form <math>k \cdot 2^n + 1</math> with <math>2^n > k</math> || <math>n = 2, k = 3</math> || {{#lst:Proth prime|list}} || | |||
|- | |||
| [[satisfies property::regular prime]] || fifth regular prime (2 is neither regular nor irregular) || {{#lst:regular prime|list}} || | |||
|} | |||
==Polynomials== | |||
===Prime-generating polynomials=== | |||
Below are some polynomials that give prime numbers for small input values, which give the value 13 for suitable input choice. | Below are some polynomials that give prime numbers for small input values, which give the value 13 for suitable input choice. | ||
Revision as of 18:08, 3 July 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.
Properties and families
| Property or family | Parameter values | First few numbers | Proof of satisfaction/membership/containment |
|---|---|---|---|
| prime number | it is the 6th prime number | 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97, [SHOW MORE]View list on OEIS | divide and check |
| Proth prime: prime of the form with | 3, 5, 13, 17, 41, 97, 113, [SHOW MORE]View list on OEIS | ||
| regular prime | fifth regular prime (2 is neither regular nor irregular) | 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 41, 43, 47, 53, 61, [SHOW MORE]View list on OEIS |
Polynomials
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 |