<|im_start|>system
You are a helpful assistant. You first think about the reasoning process in the mind and then provide the user with the answer. You should try to truely solve the question by yourself without cheating.  <|im_end|>
<|im_start|>user
 On a grid sheet, a $1 \times 5$ rectangle is initially shaded. Each minute, all unshaded cells that have at least one shaded neighboring cell are shaded. For example, after one minute, 17 cells will be shaded. How many cells will be shaded after 5 minutes? Show your work in <think> </think> tags. And return the final answer in <answer> </answer> tags.<|im_end|>
<|im_start|>assistant
Let me solve this step by step.
<think>
user
105
On a grid sheet, a $1 \times 5$ rectangle is initially shaded. Each minute, all unshaded cells that have at least one shaded neighboring cell are shaded. For example, after one minute, 17 cells will be shaded. How many cells will be shaded after 5 minutes?
test