Find the missing number
`2, 11, 45, 136, 273, ?`

Options

A. 272
B. 274
C. 273
D. 277

Explanation

To find the missing number in the series `2, 11, 45, 136, 273, ?`, we will analyze the pattern in the series step by step.

### Step 1: Identify the Pattern
We start by examining the differences between consecutive terms in the series.

- From 2 to 11:
\[ 11 - 2 = 9 \]

- From 11 to 45:
\[ 45 - 11 = 34 \]

- From 45 to 136:
\[ 136 - 45 = 91 \]

- From 136 to 273:
\[ 273 - 136 = 137 \]

### Step 2: Analyze the Differences
Now let's analyze the differences we calculated:
- The differences are: 9, 34, 91, 137.

Next, we will look at the pattern of these differences:
- From 9 to 34:
\[ 34 - 9 = 25 \]

- From 34 to 91:
\[ 91 - 34 = 57 \]

- From 91 to 137:
\[ 137 - 91 = 46 \]

### Step 3: Identify the Next Difference
We notice that the differences themselves are not following a simple arithmetic sequence. However, we can see that the differences are increasing rapidly.

### Step 4: Establish a Multiplication Pattern
Instead of focusing solely on differences, let's analyze the multiplication pattern:
- \(2 \times 5 + 1 = 11\)
- \(11 \times 4 + 1 = 45\)
- \(45 \times 3 + 1 = 136\)
- \(136 \times 2 + 1 = 273\)

### Step 5: Calculate the Next Number
Now, we can find the next term in the series using the established pattern:
- \(273 \times 1 + 1 = 273 + 1 = 274\)

### Conclusion
Thus, the missing number in the series is:
\[ \boxed{274} \]