Do we have $\mathcal O_X(1)(X)=S_1$?

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If $S$ is a graded ring which is generated by $S_1$ as an $S_0$-algebra and $X=\operatorname{Proj}S$, do we have $\mathcal O_X(1)(X)=S_1$?

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If $S$ is a polynomial ring this is Hartshorne Prop II.5.13.

If $S$ is not a polynomial ring then this is not generally true. Exercise 5.14 provides a counterexample.