9 lines
600 B
Markdown
9 lines
600 B
Markdown
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Euler's Totient function, `phi(n)` [sometimes called the phi function],
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is used to determine the number of positive numbers less than or equal to n which are relatively prime to n.
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For example, as 1, 2, 4, 5, 7, and 8, are all less than nine and relatively prime to nine, `phi(9)=6`.
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The number 1 is considered to be relatively prime to every positive number, so `phi(1)=1`.
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Interestingly, `phi(87109)=79180`, and it can be seen that `87109` is a permutation of `79180`.
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Find the value of `n`, `1 < n < 10^7`, for which `phi(n)` is a permutation of n and the ratio `n/phi(n)` produces a minimum.
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