@algorithm.ts/sieve-totient/README.md

A linear time algorithm to sieve prime numbers and get the Euler's totient function

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A typescript implementation of the **Linear Sieve** algorithm for primes numbers
and Euler's totient function.

If you are curious about this algorithm, you can visit [here][sieve-totient]
for more details.


## Install

* npm

  ```bash
  npm install --save @algorithm.ts/sieve-totient
  ```

* yarn

  ```bash
  yarn add @algorithm.ts/sieve-totient
  ```

* deno

  ```typescript
  import sieveTotient from 'https://raw.githubusercontent.com/guanghechen/algorithm.ts/main/packages/sieve-totient/src/index.ts'
  ```

## Usage

* Get all prime numbers and totient function values in the range $[2, N)$:

  ```typescript
  import sieveTotient from '@algorithm.ts/sieve-totient'

  const [totients, primes] = sieveTotient(10)
  // => 
  //    totients: [0, 1, 1, 2, 2, 4, 2, 6, 4, 6]
  //    primes: [2, 3, 5, 7]
  ```


## Related

* [Euler's totient function | Wikipedia](https://en.wikipedia.org/wiki/Euler%27s_totient_function)
* [数论基础之筛法 | 光和尘][sieve-totient]


[homepage]: https://github.com/guanghechen/algorithm.ts/tree/release-2.x.x/packages/sieve-totient#readme
[sieve-totient]: https://me.guanghechen.com/post/math/number-theory/sieve/#heading-%E7%BA%BF%E6%80%A7%E7%AD%9B-2