8 9 20 63 256 1285 ?

Options

A. 6430
B. 7450
C. 7716
D. 7746

Explanation

To solve the series: 8, 9, 20, 63, 256, 1285, we need to identify the pattern in the numbers.

### Step-by-Step Solution:

1. **Identify the first two numbers (8 and 9)**:
- To go from 8 to 9, we can use the formula:
\[ 8 \times 1 + 1 = 9 \]

2. **Next, look at the transition from 9 to 20**:
- To go from 9 to 20, we can use:
\[ 9 \times 2 + 2 = 20 \]

3. **Now, examine the transition from 20 to 63**:
- To go from 20 to 63, we can use:
\[ 20 \times 3 + 3 = 63 \]

4. **Next, analyze the transition from 63 to 256**:
- To go from 63 to 256, we can use:
\[ 63 \times 4 + 4 = 256 \]

5. **Now, we need to find the next number after 256 (which is 1285)**:
- To find the missing number, we apply the same pattern:
\[ 256 \times 5 + 5 = 1285 \]

6. **Finally, we need to find the next number after 1285**:
- We apply the pattern again:
\[ 1285 \times 6 + 6 \]
- First, calculate \(1285 \times 6\):
\[ 1285 \times 6 = 7710 \]
- Then, add 6:
\[ 7710 + 6 = 7716 \]

### Conclusion:
The missing number in the series is **7716**.