## Group: [27, 4]
## Difference Sets: 2
## Time:  0:00:00.207

return [
[ 1, 2, 3, 4, 5, 6, 9, 12, 16, 19, 20, 23, 26 ],
[ 1, 2, 3, 4, 5, 7, 8, 9, 13, 15, 18, 19, 23 ]
];

