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Consider Prime Numbers, Get Cube (Posted on 2023-10-24) Difficulty: 3 of 5
Determine all possible values of a prime number p, such that:
p2-p+1 is a perfect cube.

See The Solution Submitted by K Sengupta    
Rating: 5.0000 (1 votes)

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Solution computer solution | Comment 1 of 7
p=primes(99999999);
for i=1:length(p)
  c=p(i)^2-p(i)+1;
  cr=round(c^(1/3));
  if cr^3==c
    disp([p(i) c cr])
  end
end

tests all primes below 100 million and finds only p = 19, p^2 - p + 1 = 343, which is 7^3.

  Posted by Charlie on 2023-10-24 08:49:46
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