If a fair coin is tossed 5 times, the porbability that heads does not occur two or more times in a row is

Explanation

To solve the problem of finding the probability that heads does not occur two or more times in a row when a fair coin is tossed 5 times, we can follow these steps:

### Step 1: Define the Problem
Let \( A_n \) be the number of valid sequences of heads (H) and tails (T) of length \( n \) such that no two heads are adjacent.

### Step 2: Base Cases
We need to establish base cases for small values of \( n \):
- For \( n = 1 \): The possible sequences are H and T. Thus, \( A_1 = 2 \).
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