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<h1 id="function-combinations">Function combinations <a href="#function-combinations" title="Permalink">#</a></h1>

Compute the number of ways of picking `k` unordered outcomes from `n`
possibilities.

Combinations only takes integer arguments.
The following condition must be enforced: k <= n.


<h2 id="syntax">Syntax <a href="#syntax" title="Permalink">#</a></h2>

```js
math.combinations(n, k)
```

<h3 id="parameters">Parameters <a href="#parameters" title="Permalink">#</a></h3>

Parameter | Type | Description
--------- | ---- | -----------
`n` | number &#124; BigNumber | Total number of objects in the set
`k` | number &#124; BigNumber | Number of objects in the subset

<h3 id="returns">Returns <a href="#returns" title="Permalink">#</a></h3>

Type | Description
---- | -----------
number &#124; BigNumber | Number of possible combinations.


<h2 id="examples">Examples <a href="#examples" title="Permalink">#</a></h2>

```js
math.combinations(7, 5) // returns 21
```


<h2 id="see-also">See also <a href="#see-also" title="Permalink">#</a></h2>

[combinationsWithRep](combinationsWithRep.html),
[permutations](permutations.html),
[factorial](factorial.html)