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不知道杨老师是否注意到这个现象?

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发表于 2023-4-2 14:17 | 显示全部楼层 |阅读模式

本帖最后由 cuikun-186 于 2023-4-2 14:15 编辑


正整数     


     x        π        含1单哥        含1双哥        π/x        (π/x)^2        x*(π/x)^2
122        30        4        7         0.245901639        0.060467616        7.37704918
326        66        7        13        0.202453988        0.040987617        13.36196319
398        78        8        15        0.195979899        0.038408121        15.28643216
1718        267        21        41        0.155413271        0.024153285        41.49534342
992        167        14        28        0.168346774        0.028340636        28.11391129
***********
以上是杨传举老师给出的是其不取整时的5个反例,逻辑上应该是取整的,因为这是素数对个数是整数单位是个。

当[(π(N))^2/N]时,

r2(122)=7≥[30*30/122]=7(正确)

r2(326)=13≥[66*66/326]=13(正确)

r2(398)=15≥[78*78/398]=15(正确)

r2(1718)=41≥[267*267/1718]=41(正确)

r2(992)=28≥[167*167/992]=28(正确)

真巧了:这又是这5偶数的真值公式!

@yangchuanju

不知道杨老师能否注意到这个现象?
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