Conjugacy Classes of n-cycles in An and Their Elements

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For odd n, there are two conjugacy classes of n-cycles in the alternating group An, each containing (n-1)!/2 elements. The discussion highlights that An acts on itself, and odd permutations do not commute with n-cycles, leading to the split into two conjugacy classes. However, there is confusion regarding the terms "CCl" and "Ccl," as well as the notation used. A counterexample is provided, noting that in A3, the 3-cycles (123) and (132) commute and belong to the same conjugacy class. Clarification on these concepts and terms is necessary for a better understanding of the topic.
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(Moderator's note: thread moved from "Set Theory, Logic, Probability, Statistics")

the question is
if n is odd then there are exactly two conjugacy classes of n cycles in An each of which contains (n-1)!/2 elements.
also there is a hint says let An act on itself
i know the fact that since An acts on itself, x doesn't commute with any odd permutation. So it splits into two Ccl An (x) and CCl An (12)x(12).
But i can't figure it out how to calculate either the number of stabilizers or the number of orbits
 
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Your question is rather difficult to understand. eg. what do you mean by "CCl", "Ccl", (12)x(12)? And what is x?

I don't even think this is true! eg: in A3, the two 3-cycles: (123) and (132) commute, and so they are in the same conjugacy class.

For what it's worth, it might help you to note that if n is odd, then An contains every n-cycle, as these are even permutations. Also that the number of these n-cycles is: (n-1)! (as we can fix the 1 at the beginning of the cycle and then permute the other (n-1) numbers in every possible way).

Otherwise you will need to explain more.
 
mrbohn1 said:
Your question is rather difficult to understand. eg. what do you mean by "CCl", "Ccl", (12)x(12)? And what is x?

I don't even think this is true! eg: in A3, the two 3-cycles: (123) and (132) commute, and so they are in the same conjugacy class.

For what it's worth, it might help you to note that if n is odd, then An contains every n-cycle, as these are even permutations. Also that the number of these n-cycles is: (n-1)! (as we can fix the 1 at the beginning of the cycle and then permute the other (n-1) numbers in every possible way).

Otherwise you will need to explain more.
well the permutations you gave they are in ccl An
its what is written on my lecture notes actually i also don't know much about it but it has the same conj. class with ccl an
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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