Primes {DescTools} | R Documentation |

## Find All Primes Less Than n

### Description

Find all prime numbers aka ‘primes’ less than `n`

.

Uses an obvious sieve method and some care, working with logical and integers to be quite fast.

### Usage

```
Primes(n)
```

### Arguments

`n` |
a (typically positive integer) number. |

### Details

As the function only uses `max(n)`

, `n`

can also be a
*vector* of numbers.

### Value

numeric vector of all prime numbers `\le n`

.

### Note

This function was previously published in the package sfsmisc as `primes`

and has been integrated here without logical changes.

### Author(s)

Bill Venables (`\le n`

); Martin Maechler gained another 40% speed,
working with logicals and integers.

### See Also

### Examples

```
(p1 <- Primes(100))
system.time(p1k <- Primes(1000)) # still lightning ..
stopifnot(length(p1k) == 168)
```

[Package

*DescTools*version 0.99.55 Index]