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A comment on 7 is the largest prime followed by a cubic number. Parent comment

Re:7 is the largest prime followed by a cubic number by frankmcsherry on Monday September 03, 2018 @04:56PM (#17904822)
To be pedantic, shouldn't you also need to rule out the possibility that x is a negative number? For example, x = -1 satisfies your quadratic equation, but because we are doing an odd power of x you can rule it out.
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Re:7 is the largest prime followed by a cubic number by amluto on Monday September 03, 2018 @09:36PM (#17906017)
Aside from the 1 vs -1 issue, the proof finds all integers x such that p is prime. So I think it’s fine.
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