Find the missing number –

Pattern Analysis
The table presents two rows of numbers:

Top Row: 1, 4, 7, 12, 18

Bottom Row: 2, 20, 56, 156, ?

Let's look at the relationship between the top number (n) and the bottom number (x).

For 1 and 2: 1 * 2 = 2

For 4 and 20: 4 * 5 = 20

For 7 and 56: 7 * 8 = 56

For 12 and 156: 12 * 13 = 156

The pattern is: Bottom = Top * (Top + 1)

1 * (1 + 1) = 1 * 2 = 2

4 * (4 + 1) = 4 * 5 = 20

7 * (7 + 1) = 7 * 8 = 56

12 * (12 + 1) = 12 * 13 = 156

18 * (18 + 1) = 18 * 19 = 342

The missing number is 342, which corresponds to Option 3.