Recent content by postylem

  1. P

    Factoring x^{16}-x in F_8[x] and Proving Equivalency in F_2[x]

    Note that the polynomial factors completely into linears over \mathbb{F}_{16}. Notice that \mathbb{F}_8 is a degree 3 extension of \mathbb{F}_2, and \mathbb{F}_{16} is a degree 4, and \gcd(3,4)=1. That should get you started.
  2. P

    Permutations commuting with their powers

    Thinking of this in terms of a http://en.wikipedia.org/wiki/Group_action" is helpful. Showing that the centralizer of cycle a=(1,2,\dots,n) \in S_n, C_{S_n}(a) is equal to the group generated by the cycle of \langle a \rangle, is equivalent to showing that the stabilizer...
  3. P

    If two permutations commute they are disjoint

    oops I just realized that (12345)^2=(13524). I think you are right, Unviaje. I haven't found a proof yet though.
  4. P

    If two permutations commute they are disjoint

    Here is an example in S_5. Take \alpha=(12345), and \beta=(13524). They commute: (12345)(13524)=(14253), (13524)(12345)=(14253). But they are not disjoint (and neither is one a multiple of the other, re Unviaje).
Back
Top