Question 384316
I think I found the recursion!

We have 5 - 8 = -3. Take the absolute value of the difference, multiply by 2 to obtain the next term.

8 - 6 = 2, absolute value, multiply by 2 to get 4, etc.

In general, the sequence should be a_n = 2|a_(n-2) - a_(n-1)|. From this, the following term is 16.