回复 5# 的帖子
目前对于这个问题看到的大多是搜索最大解业余时间写了一个n生素数统计算法,
能快速算出小范围内 k-tuples 素数
在主流 2核cpu上两小时能算出 PI_4(10^14) 楼上有不具体得到“四生素数”数值,而直接得到某范围内的“四生素数”数目的算法?
愿闻其详。
回复 52# 的帖子
确切的说能算PI_X(__int64 beg, __int64 end) (1<<X<<7)<br>end < 10^15, 目前程序有bug, 正在调优当中.<br>
<pre>prime k-tuples
2-tuplet, (twin): n, n+2
3-tuplet, (triplet): n, n+2, n+6
n, n+4, n+6
4-tuplet, (quadruplet): n, n+2, n+6, n+ 8
5-tuplet, (quintuplet): n, n+2, n+6, n+ 8, n+12
n, n+4, n+6, n+10, n+12
6-tuplet, (sextuplet):n, n+4, n+6, n+10, n+12, n+16
7-tuplet, (septuplet):n, n+2, n+6, n+ 8, n+12, n+18, n+20
n, n+4, n+8, n+12, n+14, n+18, n+20
8-tuplet, (octuplet): n, n+2, n+6, n+ 8, n+12, n+18, n+20, n+26
n, n+4, n+6, n+12, n+14, n+20, n+24, n+26
n, n+6, n+8, n+14, n+18, n+20, n+24, n+26
9-tuplet, (nonuplet): n, n+2, n+6, n+ 8, n+12, n+18, n+20, n+26, n+30
n, n+2, n+6, n+ 8, n+12, n+18, n+24, n+26, n+30
n, n+6, n+8, n+14, n+18, n+20, n+24, n+26, n+30
n, n+6, n+8, n+14, n+18, n+20, n+24, n+26, n+30
部分结果如下:
n PI_2(n)t(s) PI_3(x)t(s)PI_4(x) t(s)
---------------------------------------------------------------------
| 10^9| 3424506 0.77 | 379508 0.55|28388 0.26 |(赛扬 1.3G)
0.28 0.28 0.08 |(PD 940 3.2G)
---------------------------------------------------------------------
| 10^10 |27412679 7.60 |2713347 5.44| 180529 2.00 |
2.71 2.49 0.64
---------------------------------------------------------------------
| 10^11 | 224376048 143. | 20081601 103.|1209318 25.5 |
28.26 6.88
---------------------------------------------------------------------
| 10^12 |1870585220 1315 |152839134 786.|8398278 212. |
303.0 179 60.1
| 10^13 | | |60070590 |
982.0
| 10^14 | | |441296836 |
7966
--------------------------------------------------------------------</pre> 请问哪里有“8-tuplet”等的定义?可否提供一些相关资料?比如说论文、链接等。谢谢!
回复 54# 的帖子
一些有用的链接http://anthony.d.forbes.googlepages.com/ktuplets.htm
http://hk.geocities.com/goodprimes/TTwins4.htm
http://primes.utm.edu/glossary/page.php?sort=PrimeKtupleConjecture
http://www.trnicely.net/ 好像看到都是将所有t生素数搜索出来的方法吧 tprime 在 55# 提供的链接中有一条新信息:
4104082046 * 4800# + 5651 + 0, 2, 6, 8 (2058 digits, Apr 2005, Norman Luhn, PRIMO)
而楼主(无心人)得到的资料还停留在“而且最新的结果都到了1300多位”(见41#)
我用HugeCalc展开了当前最新的“四生素数”纪录:
:*-^679699796173718124671757715485878719914075080776334093840370857801256033644556656420928619404703800588882728491060264549012233476650784789808758965448761333908352641334954171882529744998001739435088750349426039984494692001398852302105795938185398954763139738397960604343344165629411301815603209962973782611927749154559166186441717641521954423276803669948433626211555626263999296412717937388713058328406902044429597351760555007014952997095976963129380692033639887402168092909372002743794045599933735963151148250374076075157711273203454901906173207116822814236656419079587054302700050608341446632048629846718907892181134024239017996816624201337317268660276594559350595754000209744727200164037179597590015009083959616247843531425208806066907535954490760971513129018417476884416807763299026087783909215803010213368996679288766625066875248966870164081615443177186388516380073045565738057604964545980717437960149715023963973218935059131281477008008145824379032446439117036293725214970605131958628912714337492198596600481413928124316277905007766553390473892628843122444904489700831946643946464678667976183168813130066009586632127902343172804183284994182460150208669968851890503270433658358903373023197801351253182282668868493361609243999260634626848265992617351288045783230670685174888777781998112070176413572283321500054034459822918544018979156860766622421601211723807419164382270785110280896957947281858990791367106787616575483584025259504717923218459533770932377470857296979242262344794927119527364873786393107993699401532599573408747377857217322873416695117485571866324936574119168927918928553379768312064947598476338392389287341605640696416400823373219055674741550539243725492213177635282646306415281657839666979148671816078960416914684223649913811221978399438790933492976799263925809977582826568626302472098985371458987751275062874265925537989169366451611754024010370174865057535710257268298296114256758032707943611336222748478753016002086718730181182084563294437499492988008984555692188797808561793022127284670155058584472605768554251416642008288306560595271 + 0, 2, 6, 8 4104082046 * 4800# + 5651 + 0, 2, 6, 8 (2058 digits, Apr 2005, Norman Luhn, PRIMO)
楼上的结果是自编程序搜索到的,还是通过上述公式计算出来的? 原帖由 liangbch 于 2008-2-27 21:40 发表 http://bbs.emath.ac.cn/images/common/back.gif
楼上的结果是自编程序搜索到的,还是通过上述公式计算出来的?
不知你说的“结果”是指“4104082046 * 4800# + 5651 + 0, 2, 6, 8”,还是指展开成2058位数的那个?
若指前者,需发现者来回答;若为后者,则是由 HugeCalc.exe V8.0.0.0 完成的,并通过了其“素性测试”(废话)。
注:n# 表示“不大于n的所有正素数之积”;在 HugeCalc 中的函数名为“Primorial”。 :)
GxQ尝试过多大的数字的素性测试
具体时间是多少?