input/output, 1,8 2,14 3,?

y=6x+2, so 20

To find the missing value in the sequence 1, 8, 2, 14, 3, ?, we need to identify the pattern or relationship between the given numbers. Looking at the sequence, we can observe the following pattern:

The sequence is alternating between two different rules:

1st rule: Multiply the first number by 2 and add 6 to get the next number. (1 x 2 + 6 = 8)

2nd rule: Multiply the first number by 4 and subtract 6 to get the next number. (2 x 4 - 6 = 14)

Based on this pattern, to find the missing number after 3, we need to apply the first rule:

3 x 2 + 6 = 12

Therefore, the missing number is 12.