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孪生素数个数约等于{两个素数个数)的差
由哈代的孪生素数公式可知:孪生素数个数等于
```````2CN``````kN
T(N)≈-------==-----
......(LnN)^2..(LnN)^2
其中:孪生素数常数C==0.66016181....,2C=1.320324
求解此式,利用了一个重要的运算式:
实际数据验证的数内素数个数公式:
由:π(N)≈N/(LnN-1),
知:π(N)(LnN)-π(N)≈N,
即:π(N)(LnN)≈π(N)+N ,
得到了比(N/LnN)准确些的数内素数个数公式:
```````N+π(N)```N ````N
π(N)≈-------=-----+-------
........LnN.....LnN..(LnN)^2
把π(N)-N/LnN≈N/(LnN)^2代入首式:
```````2CN`````
T(N)≈-------==2C{π(N)-N/LnN}
......(LnN)^2
将精确的数内素数个数公式(N)解代入上式.
T(N)≈2C{Li(N)-N/LnN}≈1.32{Li(N)-N/LnN}.
孪生素数个数约等于1.32倍{积分公式解的素数个数与均值公式解的素数个数}
的差。
Li(x)-x/lnx________T(x)____________1.32032*[Li(x)-x/lnx]___误差
1.6________________2_______________2.1_____________________1.0939215483
8.2________________8_______________10.9____________________1.3674019353
32.2_______________35______________42.5____________________1.2160212348
160.2______________205_____________211.5___________________1.0321926543
943.1______________1224____________1245.2__________________1.0173263669
6244.5_____________8169____________8244.8__________________1.0092853775
44497.3____________58980___________58750.6_________________0.9961120788
333527.9___________440312__________440363.6________________1.0001173203
2594291.5__________3424506_________3425295.0_______________1.0002304101
20761132.0_________27412679________27411337.9______________0.9999510785
169934746.3________224376048_______224368244.2_____________0.9999652204
1416743454.7_______1870585220______1870554718.1____________0.9999836940
11992967422.8______15834664872_____15834554747.7___________0.9999930454
102838623524.9_____135780321665____135779891412.4__________0.9999968313
891606015070.2_____1177209242304___1177205253817.5_________0.9999966119
7804293059023.6____10304195697298__10304164211690.1________0.9999969444
68883742650516.8___90948839353159__90948583096330.3________0.9999971824
612483092843091.2__808675888577435_808673677142590.1_______0.9999972654
青岛 王新宇
2009.5.31
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