npm package: @stdlib/constants-float64-catalan
Description: Catalan's constant.
Author: The Stdlib Authors
Latest version: 0.2.3

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# CATALAN

[![NPM version][npm-image]][npm-url] [![Build Status][test-image]][test-url] [![Coverage Status][coverage-image]][coverage-url] <!-- [![dependencies][dependencies-image]][dependencies-url] -->

> [Catalan's constant][catalan-constant].

<section class="intro">

[Catalan's constant][catalan-constant] `C` (also denoted `K` or `G`) commonly appears in estimates of combinatorial functions and may be defined by the following infinite series

<!-- <equation class="equation" label="eq:catalan_constant" align="center" raw="C = \sum_{n=0}^{\infty} \frac{(-1)^{n}}{(2n+1)^2} = \frac{1}{1^2} - \frac{1}{3^2} + \frac{1}{5^2} - \frac{1}{7^2} + \cdots" alt="Catalan's constant"> -->

<div class="equation" align="center" data-raw-text="C = \sum_{n=0}^{\infty} \frac{(-1)^{n}}{(2n+1)^2} = \frac{1}{1^2} - \frac{1}{3^2} + \frac{1}{5^2} - \frac{1}{7^2} + \cdots" data-equation="eq:catalan_constant">
    <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@6e1cf583c4854b3d982f22f361f53a30c9f552dc/lib/node_modules/@stdlib/constants/float64/catalan/docs/img/equation_catalan_constant.svg" alt="Catalan's constant">
    <br>
</div>

<!-- </equation> -->

</section>

<!-- /.intro -->

<section class="installation">

## Installation

```bash
npm install @stdlib/constants-float64-catalan
```

</section>

<section class="usage">

## Usage

```javascript
var CATALAN = require( '@stdlib/constants-float64-catalan' );
```

#### CATALAN

[Catalan's constant][catalan-constant].

```javascript
var bool = ( CATALAN === 0.915965594177219 );
// returns true
```

</section>

<!-- /.usage -->

<section class="examples">

## Examples

<!-- TODO: better example -->

<!-- eslint no-undef: "error" -->

```javascript
var CATALAN = require( '@stdlib/constants-float64-catalan' );

console.log( CATALAN );
// => 0.915965594177219
```

</section>

<!-- /.examples -->

<!-- C interface documentation. -->

* * *

<section class="c">

## C APIs

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<section class="intro">

</section>

<!-- /.intro -->

<!-- C usage documentation. -->

<section class="usage">

### Usage

```c
#include "stdlib/constants/float64/catalan.h"
```

#### STDLIB_CONSTANT_FLOAT64_CATALAN

Macro for [Catalan's constant][catalan-constant].

</section>

<!-- /.usage -->

<!-- C API usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="notes">

</section>

<!-- /.notes -->

<!-- C API usage examples. -->

<section class="examples">

</section>

<!-- /.examples -->

</section>

<!-- /.c -->

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<section class="related">

</section>

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<section class="main-repo" >

* * *

## Notice

This package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].

#### Community

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---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

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[stdlib-license]: https://raw.githubusercontent.com/stdlib-js/constants-float64-catalan/main/LICENSE

[catalan-constant]: https://en.wikipedia.org/wiki/Catalan%27s_constant

</section>

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