There are many possible answers. The simplest solution is -20
This is the fourth term in the sequence defined by
t(n) = 8 - 7n where n = 1, 2, 3, ...
The series 1 6 10 13 15 (1+5=6; 6+4=10, 10+3=13; 13+2=15) is completed by 15+1=16. The answer is 16.
1834 (3+1)6 (4+2)9 (6+3)13 (9+4)18 (13+5)...and so on
32 Other than the first two numbers, succesive numbers are formed by adding the two previous numbers and subtracting 1. 4 + 3 - 1 = 6 3 + 6 - 1 = 8 6 + 8 - 1 = 13 8 + 13 - 1 = 20 13 + 20 - 1 = 32
13
13
18. 3+1=4, 4+2=6, 6+3=9, 9+4=13, 13+5=18.
Brothers and Sisters - 2006 Something Ida This Way Comes 1-13 is rated/received certificates of: Netherlands:6
1
7 - 6 = 1
18. The pattern is add 5, then subtract 1.
49
If you mean: 13*(x -1) +6 then it is 13x -13 +6 = 13x -7 as an expression