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+# choose
+
+Compute the
+[binomial coefficient](https://en.wikipedia.org/wiki/Binomial_coefficient),
+`n C k`.
+
+# example
+
+## repl
+
+```
+> var choose = require('choose')
+> choose(5,3)
+10
+> choose(4,4)
+1
+> choose(7,3)
+35
+```
+
+## pascal's triangle
+
+``` js
+var choose = require('choose');
+
+var count = Number(process.argv[2]) || 20;
+var rows = [];
+for (var n = 0; n < count; n++) {
+ var row = [];
+ for (var k = 0; k <= n; k++) {
+ row.push(choose(n, k));
+ }
+ rows.push(row.join(' '));
+}
+
+var len = rows[rows.length - 1].length;
+rows.forEach(function (row) {
+ var n = Math.floor((len - row.length) / 2) + 1;
+ console.log(Array(n).join(' ') + row);
+});
+```
+
+***
+
+```
+
+ 1
+ 1 1
+ 1 2 1
+ 1 3 3 1
+ 1 4 6 4 1
+ 1 5 10 10 5 1
+ 1 6 15 20 15 6 1
+ 1 7 21 35 35 21 7 1
+ 1 8 28 56 70 56 28 8 1
+ 1 9 36 84 126 126 84 36 9 1
+ 1 10 45 120 210 252 210 120 45 10 1
+ 1 11 55 165 330 462 462 330 165 55 11 1
+ 1 12 66 220 495 792 924 792 495 220 66 12 1
+ 1 13 78 286 715 1287 1716 1716 1287 715 286 78 13 1
+ 1 14 91 364 1001 2002 3003 3432 3003 2002 1001 364 91 14 1
+ 1 15 105 455 1365 3003 5005 6435 6435 5005 3003 1365 455 105 15 1
+ 1 16 120 560 1820 4368 8008 11440 12870 11440 8008 4368 1820 560 120 16 1
+ 1 17 136 680 2380 6188 12376 19448 24310 24310 19448 12376 6188 2380 680 136 17 1
+ 1 18 153 816 3060 8568 18564 31824 43758 48620 43758 31824 18564 8568 3060 816 153 18 1
+1 19 171 969 3876 11628 27132 50388 75582 92378 92378 75582 50388 27132 11628 3876 969 171 19 1
+```
+
+# methods
+
+``` js
+var choose = require('choose')
+```
+
+## choose(n, k)
+
+Return the binomial coefficient indexed by the two non-negative integers `n` and
+`k`. That is, return row `n`, index `k` of pascal's triangle.
+
+# install
+
+With [npm](http://npmjs.org) do:
+
+```
+npm install choose
+```
+
+# license
+
+MIT

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