Firepanda
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What is the number of bit permutations of the set {0,1}n and the number of circular right shifts of the set {0,1}n.
I think the number of bit permuations is 2n, so is there 4 bit permutations here? Namely (0,0), (0,1), (1,0) and (1,1).
And the right shift is just sending each element one space right isn't it?
i.e. (0,0) -> (0,0) , (0,1) -> (1,0) etc
So what does he mean by the number of shifts? 4?
Find an injective affine linear map (Z/2Z)3 -> (Z/2Z)3 that sends (1,1,1) to (0,0,0).
In my notes all I have is that
f(v) = Av + b
Here I'm trying to find A, with given v = (1,1,1) and f(v) = (0,0,0)
I also have that for this to be a bijection
=> for (Z/mZ)n -> (Z/mZ)l then n=l and gcd(det(A), m) = 1
So since this is needed for a bijection am I ok in saying this can be the criteria for it to be injective?
So if I find an A where (det(A), 2) = 1 , => det(A) can equal 1
i.e. A =
0 1 0
0 0 1
1 0 0
and so Av = (1,1,1) and now I can take b = (1,1,1) so that Av+b = (2,2,2) = (0,0,0)?
Is this all correct? Thanks.
I think the number of bit permuations is 2n, so is there 4 bit permutations here? Namely (0,0), (0,1), (1,0) and (1,1).
And the right shift is just sending each element one space right isn't it?
i.e. (0,0) -> (0,0) , (0,1) -> (1,0) etc
So what does he mean by the number of shifts? 4?
Find an injective affine linear map (Z/2Z)3 -> (Z/2Z)3 that sends (1,1,1) to (0,0,0).
In my notes all I have is that
f(v) = Av + b
Here I'm trying to find A, with given v = (1,1,1) and f(v) = (0,0,0)
I also have that for this to be a bijection
=> for (Z/mZ)n -> (Z/mZ)l then n=l and gcd(det(A), m) = 1
So since this is needed for a bijection am I ok in saying this can be the criteria for it to be injective?
So if I find an A where (det(A), 2) = 1 , => det(A) can equal 1
i.e. A =
0 1 0
0 0 1
1 0 0
and so Av = (1,1,1) and now I can take b = (1,1,1) so that Av+b = (2,2,2) = (0,0,0)?
Is this all correct? Thanks.