Sidestepping the whole parens and list-op discussion, why not just avoid the empty term in $i%100: 
perl -e '
my $i=0;
for (1..456) {
  print $i%100 ? $i%10 ? "." 
                       : int(($i%100)/10)
               : "\n\t";
  $i++;
}
print "\n";
'

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In reply to Re: print list, comma not working? by keszler
in thread print list, comma not working? by fzellinger

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