forked from course-work/week1
15 lines
844 B
Markdown
15 lines
844 B
Markdown
WTF - Write Totatives Finder
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The divisors of a number are those numbers that divide it evenly; for example, the divisors of 60 are `1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, and 60`. The sum of the divisors of 60 is 168, and the number of divisors of 60 is 12.
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The totatives of a number are those numbers less than the given number and coprime to it. Two numbers are coprime if they have no common factors other than 1.
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For example, the totatives of 30 are `1, 7, 11, 13, 17, 19, 23, and 29`.
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The number of totatives of a given number is called its totient. As you can see above, the totient of 30 is 8.
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Your task is to write a small library of five functions that compute the divisors of a number, the sum and number of its divisors, the totatives of a number, and its totient.
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_Hint_: The functions can call each other!
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