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combinatorics - How the solve the parameter of the conjugate permutations


As we know the definition of conjugate permutations is: $$\exists p \quad p^{-1} \alpha p=\beta$$ When I have an alpha=Cycles[{{1,4},{2,5,6,3}}] and a beta=Cycles[{{1,2,5,3},{4,6}}]. So how to use Mathematica to solve the $p$?



Answer



The theoretical work from This post.




Happy to show my own finP.And I'm glad to seen another better solution can do this all the same. :)


findP[Cycles[c1_], Cycles[c2_]] := 
Module[{l}, l = Sort /@ {c1, c2};

PermutationCycles /@
Map[Last,
Union[Transpose[Catenate /@ l], #] & /@
Function[list,
Transpose[{First[list], #}] & /@ Permutations[Last[list]]][
Complement[Range[Max[l]], Flatten[#]] & /@ l], {2}]]


$\color{blue}{\text{First example}}$


findP[Cycles[{{1, 4}, {2, 5, 6, 3}}], Cycles[{{1, 2, 5, 3}, {4, 6}}]]



{Cycles[{{1,4,6,5,2}}]}



verification


PermutationProduct[InversePermutation[Cycles[{{1, 4, 6, 5, 2}}]], 
Cycles[{{1, 4}, {2, 5, 6, 3}}], Cycles[{{1, 4, 6, 5, 2}}]]


Cycles[{{1, 2, 5, 3}, {4, 6}}]




$\color{blue}{\text{Second example}}$


twoP=findP[Cycles[{{1,3},{4,7,6}}],Cycles[{{1,5},{2,6,4}}]]

We get two $p$



{Cycles[{{2,3,5,7,6,4}}],Cycles[{{2,7,6,4},{3,5}}]}



verification


PermutationProduct[InversePermutation[#],Cycles[{{1,3},{4,7,6}}],#]&/@twoP



{Cycles[{{1,5},{2,6,4}}],Cycles[{{1,5},{2,6,4}}]}



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