Lemma 37.60.9. Let f : X \to S be a morphism of schemes. If S is locally Noetherian, then f is pseudo-coherent if and only if f is locally of finite type.
Proof. This translates into the following algebra result: If R \to A is a finite type ring map with R Noetherian, then R \to A is pseudo-coherent if and only if R \to A is of finite type. To see this, note that a pseudo-coherent ring map is of finite type by definition. Conversely, if R \to A is of finite type, then we can write A = R[x_1, \ldots , x_ n]/I and it follows from More on Algebra, Lemma 15.64.17 that A is pseudo-coherent as an R[x_1, \ldots , x_ n]-module, i.e., R \to A is a pseudo-coherent ring map. \square
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