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Calculation 2Time Limit: 2000/1000 MS (Java/Others)Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 1121Accepted Submission(s): 479Problem DescriptionGiven a positive integer N, your task is to calculate the sum of the positive integers less than N which are not coprime to N. A is said 阅读全文
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Farey SequenceTime Limit:1000MSMemory Limit:65536KTotal Submissions:9180Accepted:3501DescriptionThe Farey Sequence Fn for any integer n with n >= 2 is the set of irreducible rational numbers a/b with 0 < a < b <= n and gcd(a,b) = 1 arranged in increasing order. The first few areF2 = {1/2 阅读全文
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RelativesTime Limit:1000MSMemory Limit:65536KTotal Submissions:8841Accepted:4134DescriptionGiven n, a positive integer, how many positive integers less than n are relatively prime to n? Two integers a and b are relatively prime if there are no integers x > 1, y > 0, z > 0 such that a = xy a 阅读全文