2022 AMC 12B Problems/Problem 3
Problem
How many of the first ten numbers of the sequence , , , ... are prime numbers?
Solution 1
Let denote the digit written times and let denote the concatenation of , , ..., . Observe that Clearly, both terms are larger than since , hence all the numbers of the sequence are , and we're done!
See Also
2022 AMC 12B (Problems • Answer Key • Resources) | |
Preceded by Problem 2 |
Followed by Problem 4 |
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All AMC 12 Problems and Solutions |
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