# Kerodon

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Remark 2.5.6.8. The formation of Eilenberg-MacLane spaces $A \mapsto \mathrm{K}(A,n)$ is defined for every integer $n$. However, it is only interesting for $n \geq 0$: if $n$ is negative, then the simplicial abelian group $\mathrm{K}(A,n)$ is trivial (that is, it is isomorphic to $\Delta ^0$ as a simplicial set).