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<head><title>binomial -- binomial coefficient</title>
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<div><h1>binomial -- binomial coefficient</h1>
<div class="single"><h2>Synopsis</h2>
<ul><li><div class="list"><dl class="element"><dt class="heading">Usage: </dt><dd class="value"><div><tt>binomial(n,k)</tt></div>
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<li><div class="single">Inputs:<ul><li><span><tt>n</tt>, <span>an <a href="___Z__Z.html">integer</a></span></span></li>
<li><span><tt>k</tt>, <span>an <a href="___Z__Z.html">integer</a></span>, , must be non-negative</span></li>
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<li><div class="single">Outputs:<ul><li><span><span>an <a href="___Z__Z.html">integer</a></span>, the binomial coefficient, the coefficient of <tt>x^k</tt> in <tt>(1+x)^n</tt></span></li>
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<div class="single"><h2>Description</h2>
<div><table class="examples"><tr><td><pre>i1 : binomial(13,6)
o1 = 1716</pre>
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<tr><td><pre>i2 : binomial(-1,3)
o2 = -1</pre>
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<div class="single"><h2>Caveat</h2>
<div>Doesn't do polynomials, things like <tt>binomial(x,3)</tt> where <tt>x</tt> is an element of a ring other than<tt> ZZ</tt></div>
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<div class="waystouse"><h2>Ways to use <tt>binomial</tt> :</h2>
<ul><li>binomial(ZZ,ZZ)</li>
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