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楼主 |
发表于 2016-10-25 08:46
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接:500(1-1/2)(1-2/3)(1-2/5)(1-2/7)(1-2/11)(1-2/13)(1-2/17)(1-2/19)(1-2/23)(1-2/29)(1-2/31)
=500(1/2)(1/3)(3/5)(5/7)(9/11)(11/13)(15/17)(17/19)(21/23)(17/29)(29/31)
=15.522880456
实际有22组,去掉3,997 17,983. 23,977. 29,971. 四组,还有18组,18大于15啊
加强筛为:500(1-4/7)(1-13/36-13/36)(1-2/3)(1-2/5)(1-2/7)(1-2/11)(1-2/13)(1-2/17)(1-2/19)(1-2/23)(1-2/29)
=3.96508152228
比15小多了 |
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