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Tight closure/Generische Schranke/Parametersituation/Beispiel/en

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Suppose that  n=d+1  in the situation of Fakt. Then the generic elements f1,,fd+1 are parameters. In the polynomial ring  P=K[x0,x1,,xd]  we have for parameters of degree a1,,ad+1 the inclusion

Pi=0daid(f1,,fd+1),

because the graded Koszul resolution ends in R(i=0dai) and

(H𝔪d+1(P))k=0 for kd.

So the theorem implies for a graded ring R finite over P that  (f1,,fd+1)  holds for generic elements. But by the graded Briançon-Skoda Theorem (see Fakt) this holds for parameters even without the generic assumption.