**Answer:**

This is an example of so called mixed sequence. There are two parts. The numbers on even spaces are 10,9,8,7,6 and the numbers on odd spaces are 1,3,6,7,9 :

1, **10**, 3, **9**, 5, **8**, 7, **7**, 9, **6** …

So, the next numbers are 11, 5, 13, 4, 15, 3

I like to ask this question to see if candidate can think outside the box or he would be locked into assumption that there is a single sequence answer.