Permutations

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Shuffling

\((a,b,c)\)

\((a,c,b)\)

\((b,a,c)\)

\((b,c,a)\)

\((c,a,b)\)

\((c,b,a)\)

Actions

\((0, 1, 2) \rightarrow (0,1,2)\)

\((0, 1, 2) \rightarrow (0,2,1)\)

\((0, 1, 2) \rightarrow (1,0,2)\)

\((0, 1, 2) \rightarrow (1,2,0)\)

\((0, 1, 2) \rightarrow (2,0,1)\)

\((0, 1, 2) \rightarrow (2,1,0)\)

Positional Notation

Apply \((1,0,2)\) to \((a,b,c)\) giving \((b,a,c)\).

Sometimes written as

\(\begin{pmatrix} 0 & 1 & 2 \\ 1 & 0 & 2 \end{pmatrix}\)

Combining Permutations

Apply \((1, 0, 2)(2, 1, 0)\) to \((a,b,c)\).

First, apply \((2,1,0)\) to \((a,b,c)\) giving \((c,b,a)\).

Then apply \((1,0,2)\) to \((c,b,a)\) giving \((b,c,a)\)

Note that we can apply \((1,0,2)\) to \((2,1,0)\) giving \((1,2,0)\).

See \((1,2,0)\) applied to \((a,b,c)\) also gives \((b,c,a)\).