Prove that k-cube graph is a Cayley graph

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Define Cayley graph as following:

G is finite group. C $\subseteq$ G such that C does not contain identity element of G and g-1 $\in$ C for all g $\in$ C. Cayley graph X(G,C) is formed with vertices V(X)=G, edges E(X)={(a,b): a,b $\in$ G, ab-1 $\in$ C}.

The k-cube is the graph with vertex set {0,1}k such that any two vertices x,y $\in$ {0,1}k are joined by an edge if and only if x and y differ in exactly one coordinate. Show that the k-cube is a Cayley graph.

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Hint: Try $G=\mathbb Z_2^k$ and let $C$ be the set of $k$-tuples with $1$ in one coordinate and $0$ in every other.

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I work this out with your hint.

I have g={0,1}k. The operation in G is addtion modulo 2.

g-1=g, e={0}k

So the vertices are a,b $\in$ G.

There is edge (a,b) if a*b=ej=(x1,x2,...,xk) where xj=1, 1 $\leq$ j $\leq$ k and xi=0 for all i$\neq$j

In this case a*b-1=a*b

So C={ej, j=1,2,...,k}