my @prev = (0,0,0);
my @n    = (0,0,0);
my $num = 0;
{
    $n[0] = ++$num;
    $n[1] = $b36->to_base($num);
    $n[2] = $b64->to_base($num);
    if( grep { $prev[$_] < length($n[$_]) } 0..2 ) {
        print join( ' ', @n ), "\n";
    }
    $prev[$_] = length($n[$_]) for 0..2;
    redo;
}