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AlffClassGroupGenBoundStrong
Return a bound for the degree of prime divisors which generate
the divisor class group.
Syntax:
b := AlffClassGroupGenBoundStrong(F);
integer |
b |
generation bound |
alff |
F |
global function field |
See also: AlffClassGroupGenBound, AlffClassGroupProdBound, AlffClassGroup, AlffInit, AlffOrders
Description:
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 <= b. This function computes
b <= \lceil 2 \log_q(4g-2) rceil
using information on the number of places of F of bounded degree
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.
Example:
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