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Dear GAP Forum,

I have found a bug in GAP 4,

which may lead to wrong results of the function

`TransformingPermutationsCharacterTables'.

This function may return `fail' in some cases where in fact the

given character tables are permutation equivalent.

If a record is returned by this function then this result is correct.

The underlying function for computing the equivalence of *matrices*

is not affected by this problem.

I do not know how probable a wrong result is, but I did not get

suspicious over the years since the first release of GAP 4.

(For those who are interested in the background:

The GAP 3 function `PermGroupOps.ElementProperty' took an optional

third argument, and the GAP 4 function `ElementProperty' takes

one more optional argument.

The third argument in GAP 3 corresponds to the *fourth* argument in GAP 4,

and this changed behaviour was not taken into account when the code

of `TransformingPermutationsCharacterTables' was translated from

GAP 3 to GAP 4.)

Sorry for the inconveniences,

and kind regards

Thomas Breuer

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