The game isn't that bad, a bit simple maybe. Though it could do with clearer instructions.
Here is my take on the instruction (bare in mind that I found this out by playing):
First the game will give you three numbers, type them in AFTER the game finishes telling you (it annoyingly dictates your numbers back to you, try to ignore it), then it will give you another three numbers (and call it a new level), once you complete these it will give you the same three followed be a new one, then it gives you a new three numbers (ie another level), each level the number if numbers you will reach will increase (I got to 12 :D ).
For example it could look something like this:
Level 1: 1,2,3
Level 2: 5,3,2 then 5,3,2,6
Level 3: 3,2,5 then 3,2,5,1 then 3,2,5,1,2
Completing each one faster earns more (bonus) points.
Now that you know how to play, try it again!
(Good luck)