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Old 2019-10-02, 11:57   #1
enzocreti
 
Mar 2018

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Default isomorphism

Let be E the parity function S(n) in -1,+1


where S(n) are the permutations.


S(n)/A(n) is the quotient Group where A(n) denotes Ker E


so the quotient Group is given by the right (left cosets)of odd and even permutations?
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Old 2019-10-02, 12:07   #2
Nick
 
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Yes, as long as n is at least 2, that quotient group has 2 elements: the set of all even pemutations and the set of all odd permutations.
These are the 2 cosets of A(n) in S(n).
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Old 2019-10-02, 12:19   #3
enzocreti
 
Mar 2018

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Default isomorphism

so it follows that S(n)/A(n) is isomorphic to the Group (-1,+1)?
by the fundamental theorem of isomorphism?
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Old 2019-10-02, 14:38   #4
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Quote:
Originally Posted by enzocreti View Post
so it follows that S(n)/A(n) is isomorphic to the Group (-1,+1)?
by the fundamental theorem of isomorphism?
Yes, for all n≥2, that's right.
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Old 2019-10-03, 06:30   #5
enzocreti
 
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Default isomorphism

ok thanks
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