Definition 18.5.1. Let $\mathcal{C}$ be a site. Let $\mathcal{G}$ be a presheaf of sets. The free abelian sheaf $\mathbf{Z}_\mathcal {G}^\#$ on $\mathcal{G}$ is the abelian sheaf $\mathbf{Z}_\mathcal {G}^\#$ which is the sheafification of the free abelian presheaf on $\mathcal{G}$. In the special case $\mathcal{G} = h_ X$ of a representable presheaf associated to an object $X$ of $\mathcal{C}$ we use the notation $\mathbf{Z}_ X^\#$.

Comment #4345 by Manuel Hoff on

I think there is a word missing in the second sentence: ...which is the sheafification of the free abelian presheaf on $\mathcal G$.

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