Find all positive integers such that the product of the first primes increased by 1 is a power of an integer (with an exponent greater than 1).
Solution
Denote the first primes as
Suppose that for some integers . We can assume WLOG that is prime since . Obviously, has no prime factors not exceeding , so and consequently is one of the first primes. Now , which implies , but then by Lifting the Exponent Lemma
This is a contradiction, as is not divisible by the square of any prime. Thus, there does not exist any satisfying the problem. □
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