27.
5
456789
26 As far as I can tell the sequence is +10,-5,+10,-5.
21
27.
5
10
5
10
456789
26 As far as I can tell the sequence is +10,-5,+10,-5.
5
21
it is 7
10
This is a peculiar number sequence which follows the following rule: +7, -4, +8, -3, +9, -2... The next few functions would be +10, -1, +11, -0 And thus the next few numbers in the sequence would be 17+10=27, 27-1=26, and so on. The sequence in total goes 2, 9, 5, 13, 10, 19, 17, 27, 26, 37, 37.