# Kerodon

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Construction 2.5.6.7 (Eilenberg-MacLane Spaces). Let $A$ be an abelian group, let $n$ be an integer, and let $A[n]$ denote the chain complex consisting of the single abelian group $A$, concentrated in degree $n$ (Example 2.5.1.2). We will denote the simplicial abelian group $\mathrm{K}( A[n] )$ by $\mathrm{K}(A,n)$ and refer to it as the $n$th Eilenberg-MacLane space of $A$.