求助：为什么不能显示图形？

matlab666

想动画显示散列图，却没有显示
7 b6 l* j, d. W. L% z2 ^Clear[tt]
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: {  w+ I2 p: X: d- J* c3 q  W, W. ptt = {1, 1/2^2, 1/3^2}

{1,1/4,1/9}
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Do[ListPlot[tt = Append[tt, 1/i^2]], {i, 4, 20}]
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matlab666

自己动手，丰衣足食--问题已解决
Clear[tt];
tt = {1, 1/2^2, 1/3^2};
7 O+ [/ l1 h2 V7 s4 x4 W4 a1 ?Do[tt = Append[tt, N[1/i^2]];
# x" L9 y: v% y  i9 B4 t Print[ListPlot[tt, PlotRange -> {0, 1},
   PlotStyle -> PointSize[0.02]]], {i, 4, 20}]
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