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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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