How many rows of Pascal's Triangle contain the number $43$?
<|im_start|>system
You are a helpful assistant.<|im_end|>
<|im_start|>user
How many rows of Pascal's Triangle contain the number $43$?
Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
<|im_start|>assistant

user
1
How many rows of Pascal's Triangle contain the number $43$?
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