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Dear Gap-Forum.

I noticed a little bug in the function 'SortCharactersCharTable'.

This function, if called in the form

'SortCharactersCharTable( <tbl> )'

with a character table <tbl> as its only argument, is supposed to sort

the characters in '<tbl>.irreducibles' and then to apply the same

permutation to the list '<tbl>.irredinfo'.

This doesn't work right if the 1-character is not the first one in the

list 'irreducibles' and the table contains more than one character of

degree one!

gap> c2:= CharTable("Symmetric", 2);;

gap> DisplayCharTable(c2);

S22 1 11a 2a 2P 1a 1aX.1 1 -1 X.2 1 1 gap> c2.irredinfo; [ rec( charparam := [ 1, [ 1, 1 ] ] ), rec( charparam := [ 1, [ 2 ] ] ) ] gap> SortCharactersCharTable(c2); (1,2) gap> DisplayCharTable(c2); S22 1 11a 2a 2P 1a 1aX.1 1 1 X.2 1 -1 gap> c2.irredinfo; [ rec( charparam := [ 1, [ 1, 1 ] ] ), rec( charparam := [ 1, [ 1, 1 ] ] ) ]

This will be fixed in the next upgrade.

(The form 'SortCharactersCharTable( <tbl>, <perm> )' with an explicit

permutation as second argument, as suggested in the answer to Kay

Magaard's letter, works.)

Goetz Pfeiffer.

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