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A comment on Prime Number Spiral. Parent comment

Re:Prime Number Spiral by banku_brougham on Monday January 02, 2017 @01:23AM (#13299434)
I appreciate what you are saying, but noise looks like noise. Here's an example of a useful pattern: the blank line extending to the right from zero, corresponding to the numbers {n^2 | n in 1,2,3,...} and below it {n^2-1 | n in 1,2,3,...}.

Such a great example of a visualization helping to illuminate the abstract truths in numbers. Its obvious to most people that {n^2} contains no primes. Is it obvious that {n^2-1} doesnt't either?

(except where n=2)

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Re:Prime Number Spiral by pwdisswordfish on Monday January 02, 2017 @09:09AM (#13301193)
n² - 1 = (n - 1)(n + 1)
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Re:Prime Number Spiral by banku_brougham on Tuesday January 03, 2017 @12:40PM (#13311004)
precisely. maybe its a trivial example, but if no mathematician had discovered the factorization of n^2 - 1, this visualization device would have been a helpful clue.
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