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Dear GAP-Forum,

This is to announce bugfix number 1 for GAP 4b5. The priority of this fix

is high.

You should not apply this fix to any version of GAP3.

This fix corrects:

1) A problem in the ordering of vector spaces.

2) An error in `CompositionSeries' for permutation groups.

3) A problem with the `NiceMonomorphism' of automorphism groups of

permutation groups.

4) An error with trivial generators of subgroups of FpGroups.

5) A problem with computing permutation representations of certain perfect

groups.

6) An error in the element test for SU(n,q)

7) A wrong character table of 6.Suz mod 7

8) An error in the `Append' routine for vectors over GF(2)

9) An error in the kernel function `BlistList' when applied to ranges with

increment >1.

10) A missing method for `ElementaryAbelianGroup' as permutation group.

11) A problem in the arithmetic of Laurent Polynomials.

12) It also adds a subdirectory to the `example' share package that has been

accidentally forgotten.

Errors 1,5,6,7,8 and 9 might lead to wrong results,

errors 2-4, and 10-12 will lead to error messages.

Many thanks to:

Ken Brown for reporting error number 4, Akihide Hanaki for reporting error 6,

William Husen for reporting error 7, Stefan Kohl for reporting errors 9 and 10,

Tom McDonough for reporting error 11.

Load the zoo archive 'fix4b5n1.zoo' from the bugfixes web page

http://www-gap.dcs.st-and.ac.uk/~gap/Info4/bugfixes.html

Alternatively you can find this file in the 'bugfixes' directory of the

GAP4 ftp distribution.

Unpack the file in the home directory of your GAP distribution (the

directory containing the 'lib' and 'grp' directories) using

'unzoo -x fix4b5n1.zoo'

(On a PC or a Mac you will have to copy `unzoo' in the same directory and

enter the argument line after the call to 'unzoo'.) This will replace the

erraneous file by fixed versions.

Make sure you have write permissions when applying the fix.

This fix changes the kernel. You have to recompile by calling `make' in the

directory in which you unpacked the fix. Windows users can find a new binary

in the file win4b5f1.zoo in the `bugfixes' directory.

You can remove the file 'description1' afterwards.

Alexander Hulpke, 13-Jan-99

############################################################################# ## ## These commands should run without error if the fix has been applied. ## U1:= VectorSpace( Rationals, [ [ 0, 0, 1 ], [ 1, 1, 0 ] ] ); U2:= VectorSpace( Rationals, [ [ 0, 1, 0 ], [ 1, 0, 0 ] ] );; if U1 > U2 then Error("ordering"); fi; a4:=Group((1,2,3),(2,3,4)); ConjugacyClassesSubgroups(AutomorphismGroup(a4)); PerfectGroup(IsPermGroup,51888,1); PerfectGroup(IsPermGroup,322560,1); g:=PerfectGroup(168); x:=One(g); y:=One(g); Size(Group(x,y)); g:=SU(3,3); g.1 in g; ElementaryAbelianGroup(IsPermGroup,64); p:=PerfectGroup(IsPermGroup,384000,1); if Size(p)<>Size(Group(GeneratorsOfGroup(p))) then Error("size"); fi; even := [4,6..20]; l := BlistList([1..20],even); if l<>[ false, false, false, true, false, true, false, true, false, true, false, true, false, true, false, true, false, true, false, true ] then Error("blist"); fi; F:=GF(2); G := PolynomialRing(F,["u"]); u := IndeterminatesOfPolynomialRing(G)[1]; p:=u^0+u^2+u^5; p:=u^(-10)*p; p:=p*u^(-10); p:=p/u^10; q:=u^(-8)+u^4; p*q;

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