It didn't work out as I intended with a nice table to show what was happening.
The difference between 8 and 2 is 6, 2 and 3 is 1.
Add 6 and 1 = 7 missing number. multiply by next number 8
7 x 8 =56
Jump to next series of numbers
The difference between 8 and 3 is 5, 3 and 9 is 6 which equals the 56 from 7x8.
Add 5 and 6 = 11 which could be the next number in the process