undetermined:=
[
    <9, [ 1711, 1712, 1713, 1714, 1715, 1716, 1960 ]>,
    <10, [ 983, 985, 986, 989, 991, 994, 997, 1001, 1245, 1246, 1247 ]>,
    <11, [ 520 ]>
];