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<p>&nbsp;<p>
<hr noshade size="5">
<h2><a name="AlffClassGroupGenBound"></a>
AlffClassGroupGenBound
</h2>

Returns a bound for the degree of prime divisors which generate the
divisor class group.

<p><p>

<h3>
Syntax:
</h3>
<pre>b := AlffClassGroupGenBound(q, g);
b := AlffClassGroupGenBound(F);</pre>

<p>

<table>
<tr>
<td>integer</td>
<td><pre>  b  </pre></td>
<td>generation bound</td>
</tr>
<tr>
<td>integers</td>
<td><pre>  q, g  </pre></td>
<td>exact constant field size and genus of F</td>
</tr>
<tr>
<td>alff</td>
<td><pre>  F  </pre></td>
<td>global function field</td>
</tr>
</table>

<p>


See also:&nbsp;&nbsp;<a href="kashref.html#AlffClassGroupGenBoundStrong">AlffClassGroupGenBoundStrong</a>, <a href="kashref.html#AlffClassGroupProdBound">AlffClassGroupProdBound</a>, <a href="kashref.html#AlffClassGroup">AlffClassGroup</a>, <a href="kashref.html#AlffPlacesNum">AlffPlacesNum</a>, <a href="kashref.html#AlffInit">AlffInit</a>, <a href="kashref.html#AlffOrders">AlffOrders</a>, <a href="kashref.html#AlffGenus">AlffGenus</a>

<p>

<h3>
Description:
</h3>
Let F/k be a global function field of genus g over the exact
constant field of q elements, let A_1 be a divisor of
degree one and let S be the set of prime
divisors of degree  &lt;=  b. This function computes
b  &lt;=  \lceil 2 \log_q(4g-2) rceil
without using further information on F such that
the classes of the elements of
S cup {rm supp}(A_1) generate the divisor
class group of F/k. See He2 for details.

<p><p>

<p>
<hr>
<p>
<h3>
Example:
</h3>

<pre>

</pre>

<p>


<hr>

<p>
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