reduce-historical: r37

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<A NAME=LaguerreP>

<TITLE>LaguerreP</TITLE></A>
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<B>LAGUERREP</B> _ _ _  _ _ _  _ _ _  _ _ _ <B>operator</B><P>
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The <em>LaguerreP</em> operator computes the nth Laguerre Polynomial. 
The two argument call of LaguerreP is a (common) abbreviation of 
LaguerreP(n,0,x). 
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syntax: </H3>
<em>LaguerreP</em>(&lt;integer&gt;,&lt;expression&gt;) or 
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<em>LaguerreP</em>(&lt;integer&gt;,&lt;expression&gt;,&lt;expression&gt;) 
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examples: </H3>
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LaguerreP(3,xx); 

       3        2
  (- xx   + 9*xx   - 18*xx + 6)/6



LaguerreP(2,3,4); 

  -2

</TT></PRE><P>Laguerre polynomials are computed using the recurrence relation: 
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LaguerreP(n,a,x) := (2n+a-1-x)/n*LaguerreP(n-1,a,x) - 
 (n+a-1) * LaguerreP(n-2,a,x) with 
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LaguerreP(0,a,x) := 1 and LaguerreP(2,a,x) := -x+1+a 
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