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PlotDelta. This plot illustrates normalized fluctuations of the primecounting function pi pi mathrm li pi mathrm li LogLinearPlot PrimePix RiemannRx ArcTanPi Logx LogIntegralx RiemannRx ArcTanPi Logx Exp PlotPoints PlotRange All PlotStyle Red Blue AxesOrigin AspectRatio AxesStyle Thick TicksStyle DirectiveThick