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A comment on Math Team. Parent comment

Re:Math Team by lupire on Wednesday December 20, 2023 @08:33PM (#38716044)
What's especially fascinating is that the core of the problem is a generalization of the totient computation, so understanding the inclusion-exclusion construction of totient is very helpful to the problem, while simply memorizing the formula is a misdirection.

OP missing this point shows that he really was doing this for all the wrong reasons. He should have done FIRST or science bowl instead.

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Re:Math Team by jhshah on Wednesday December 20, 2023 @08:55PM (#38716162)
Completely agree, I also liked the problem and thought it was conceptual as far as these things go.

Asking for N mod 1000 was another cute twist that was meant to get you thinking about the divisibility properties of the totient function - "hmm, so (p-1) always divides \phi(n) for all prime factors p of n, how convenient..."

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Re:Math Team by chrchang523 on Wednesday December 20, 2023 @10:52PM (#38716805)
The mod 1000 is actually a consequence of the test format: all answers are integers in [0, 999], you fill in 3 digit-bubbles.
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Re:Math Team by lupire on Thursday December 21, 2023 @07:43AM (#38719751)
That's a cute coincidence that 1000 divides (11-1)(101-1), but I doubt it was intentional. The test writers didn't have much choice unless they chose a different base than 5+5.
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