Star refinement: Difference between revisions
Jump to navigation
Jump to search
en>David Eppstein m authorlink James Dugundji |
en>Addbot m Bot: Migrating 1 interwiki links, now provided by Wikidata on d:q7601285 |
||
| Line 1: | Line 1: | ||
{{For|Mertens' theorem on convergence of Cauchy products of series|Cauchy_product#Convergence_and_Mertens.27_theorem}} | |||
In [[number theory]], '''Mertens' theorems''' are three 1874 results related to the density of [[prime number]]s proved by [[Franz Mertens]].<ref name="Mertens">F. Mertens. J. reine angew. Math. 78 (1874), 46-62 [http://gdz.sub.uni-goettingen.de/dms/load/img/?PPN=PPN243919689_0078&DMDID=dmdlog5 Ein Beitrag zur analytischen Zahlentheorie]</ref> "Mertens' theorem" may also refer to his theorem in [[mathematical analysis|analysis]]. | |||
== In number theory == | |||
In the following, let <math>p\le n</math> mean all primes not exceeding ''n''. | |||
'''Mertens' 1st theorem''': | |||
:<math> \sum_{p \le n} \frac{\ln p}{p} - \ln n</math> | |||
does not exceed 2 in absolute value for every <math> n\ge 2</math>. | |||
'''Mertens' 2nd theorem''': | |||
:<math>\lim_{n\to\infty}\left(\sum_{p\le n}\frac1p -\ln\ln n-M\right) =0,</math> | |||
where ''M'' is the [[Meissel–Mertens constant]]. More precisely, Mertens<ref name="Mertens"/> proves that the expression under the limit does not in absolute value exceed | |||
:<math> \frac 4{\ln(n+1)} +\frac 2{n\ln n}</math> | |||
for every <math> n\ge 2</math>. | |||
'''Mertens' 3rd theorem''': | |||
:<math>\lim_{n\to\infty}\ln n\prod_{p\le n}\left(1-\frac1p\right)=e^{-\gamma},</math> | |||
where γ is the [[Euler–Mascheroni constant]]. | |||
=== Changes in sign === | |||
In a paper <ref>{{Cite journal |last=Robin |first=G. |lastauthoramp=yes |year=1983 |title=Sur l’ordre maximum de la fonction somme des diviseurs |journal=Séminaire Delange–Pisot–Poitou, Théorie des nombres (1981–1982). Progress in Mathematics|volume=38 |issue= |pages=233–244 |doi= }}</ref> on the growth rate of the [[Divisor function#Approximate growth rate|sum-of-divisors function]] published in 1983, [[Guy Robin]] proved that in Mertens' 2nd theorem the difference | |||
:<math>\sum_{p\le n}\frac1p -\ln\ln n-M</math> | |||
changes sign infinitely often, and that in Mertens' 3rd theorem the difference | |||
:<math>\ln n\prod_{p\le n}\left(1-\frac1p\right)-e^{-\gamma}</math> | |||
changes sign infinitely often. Robin's results are analogous to [[John Edensor Littlewood|Littlewood]]'s [[Skewes number#Skewes' numbers|famous theorem]] that the difference π(''x'') − li(''x'') changes sign infinitely often. No analog of the [[Skewes number]] (an upper bound on the first [[natural number]] ''x'' for which π(''x'') > li(''x'')) is known in the case of Mertens' 2nd and 3rd theorems. | |||
=== Mertens' second theorem and the prime number theorem === | |||
Regarding this asymptotic formula Mertens refers in his paper to "two curious formula of Legendre",<ref name="Mertens"/> the first one being Mertens' second theorem's prototype (and the second one being Mertens' third theorem's prototype: see the very first lines of the paper). He recalls that it is contained in Legendre's third edition of his "Théorie des nombres" (1830; it is in fact already mentioned in the second edition, 1808), and also that a more elaborate version was proved by [[Pafnuty Chebyshev|Chebyshev]] in 1851.<ref>P.L. Tchebychev. Sur la fonction qui détermine la totalité des nombres premiers. Mémoires présentés à l'Académie Impériale des Sciences de St-Pétersbourg par divers savants, VI 1851, 141-157</ref> Note that, already in 1737, [[Leonhard Euler|Euler]] knew the asymptotic behaviour of this sum.<ref>Leonhard Euler. Variae observationes circa series infinitas. Commentarii academiae scientiarum Petropolitanae 9 (1737), 160-188.</ref> | |||
Mertens diplomatically describes his proof as more precise and rigorous. In reality none of the previous proofs is acceptable by modern standards: Euler's computations involve the infinity (and the hyperbolic logarithm of infinity, and the logarithm of the logarithm of infinity!); Legendre's argument is heuristic; and Chebyshev's proof, although perfectly sound, makes use of the Legendre-Gauss conjecture, which will be proved in 1896 and then be better known as the [[prime number theorem]]. | |||
Mertens' proof does not appeal to any unproved hypothesis (in 1874), and only to elementary real analysis. It comes 22 years before the first proof of the prime number theorem which, on the other hand, will heavily exploit the behaviour of the [[Riemann zeta function]] in the complex plane. | |||
It is in that respect a remarkable proof. Indeed, with [[Big O notation|modern notation]] it yields | |||
<math>\sum_{p\le x}\frac1p=\log\log x+M+O(1/\log x)</math> | |||
whereas the prime number theorem (in its simplest form, without error estimate), can be shown to be equivalent to<ref>Although this equivalence is not explicitly mentioned there,it can for instance be easily derived from the material in chapter I.3 of: G. Tenenbaum. Introduction to analytic and probabilistic number theory. Translated from the second French edition (1995) by C. B. Thomas. Cambridge Studies in Advanced Mathematics, 46. Cambridge University Press, Cambridge,1995.</ref> | |||
<math>\sum_{p\le x}\frac1p=\log\log x+M+o(1/\log x).</math> | |||
== In summability theory == | |||
In [[summability theory]], '''Mertens' theorem''' states that if a real or complex [[series (mathematics)|infinite series]] | |||
:<math>\sum_{n=1}^\infty a_n</math> | |||
[[convergent series|converges]] to ''A'' and another | |||
:<math>\sum_{n=1}^\infty b_n</math> | |||
[[absolute convergence|converges absolutely]] to ''B'' then their [[Cauchy product]] [[Convergent series|converges]] to ''AB''. | |||
==References== | |||
<references/> | |||
==Further reading== | |||
*[[Akiva Moiseevich Yaglom|Yaglom]] and [[Isaak Moiseevich Yaglom|Yaglom]] ''Challenging mathematical problems with elementary solutions'' Vol 2, problems 171, 173, 174 | |||
==External links== | |||
*{{MathWorld|urlname=MertensConstant|title=Mertens Constant}} | |||
*{{MathWorld|urlname=MertensTheorem|title=Mertens Theorem|author=Sondow, Jonathan and Weisstein, Eric W.}} | |||
*{{MathWorld|urlname=MertensSecondTheorem|title=Mertens' Second Theorem}} | |||
[[Category:Mathematical series]] | |||
[[Category:Summability theory]] | |||
[[Category:Theorems about prime numbers]] | |||
Latest revision as of 09:30, 23 March 2013
28 year-old Painting Investments Worker Truman from Regina, usually spends time with pastimes for instance interior design, property developers in new launch ec Singapore and writing. Last month just traveled to City of the Renaissance.
In number theory, Mertens' theorems are three 1874 results related to the density of prime numbers proved by Franz Mertens.[1] "Mertens' theorem" may also refer to his theorem in analysis.
In number theory
In the following, let mean all primes not exceeding n.
Mertens' 1st theorem:
does not exceed 2 in absolute value for every .
Mertens' 2nd theorem:
where M is the Meissel–Mertens constant. More precisely, Mertens[1] proves that the expression under the limit does not in absolute value exceed
for every .
Mertens' 3rd theorem:
where γ is the Euler–Mascheroni constant.
Changes in sign
In a paper [2] on the growth rate of the sum-of-divisors function published in 1983, Guy Robin proved that in Mertens' 2nd theorem the difference
changes sign infinitely often, and that in Mertens' 3rd theorem the difference
changes sign infinitely often. Robin's results are analogous to Littlewood's famous theorem that the difference π(x) − li(x) changes sign infinitely often. No analog of the Skewes number (an upper bound on the first natural number x for which π(x) > li(x)) is known in the case of Mertens' 2nd and 3rd theorems.
Mertens' second theorem and the prime number theorem
Regarding this asymptotic formula Mertens refers in his paper to "two curious formula of Legendre",[1] the first one being Mertens' second theorem's prototype (and the second one being Mertens' third theorem's prototype: see the very first lines of the paper). He recalls that it is contained in Legendre's third edition of his "Théorie des nombres" (1830; it is in fact already mentioned in the second edition, 1808), and also that a more elaborate version was proved by Chebyshev in 1851.[3] Note that, already in 1737, Euler knew the asymptotic behaviour of this sum.[4]
Mertens diplomatically describes his proof as more precise and rigorous. In reality none of the previous proofs is acceptable by modern standards: Euler's computations involve the infinity (and the hyperbolic logarithm of infinity, and the logarithm of the logarithm of infinity!); Legendre's argument is heuristic; and Chebyshev's proof, although perfectly sound, makes use of the Legendre-Gauss conjecture, which will be proved in 1896 and then be better known as the prime number theorem.
Mertens' proof does not appeal to any unproved hypothesis (in 1874), and only to elementary real analysis. It comes 22 years before the first proof of the prime number theorem which, on the other hand, will heavily exploit the behaviour of the Riemann zeta function in the complex plane. It is in that respect a remarkable proof. Indeed, with modern notation it yields
whereas the prime number theorem (in its simplest form, without error estimate), can be shown to be equivalent to[5]
In summability theory
In summability theory, Mertens' theorem states that if a real or complex infinite series
converges to A and another
converges absolutely to B then their Cauchy product converges to AB.
References
- ↑ 1.0 1.1 1.2 F. Mertens. J. reine angew. Math. 78 (1874), 46-62 Ein Beitrag zur analytischen Zahlentheorie
- ↑ One of the biggest reasons investing in a Singapore new launch is an effective things is as a result of it is doable to be lent massive quantities of money at very low interest rates that you should utilize to purchase it. Then, if property values continue to go up, then you'll get a really high return on funding (ROI). Simply make sure you purchase one of the higher properties, reminiscent of the ones at Fernvale the Riverbank or any Singapore landed property Get Earnings by means of Renting
In its statement, the singapore property listing - website link, government claimed that the majority citizens buying their first residence won't be hurt by the new measures. Some concessions can even be prolonged to chose teams of consumers, similar to married couples with a minimum of one Singaporean partner who are purchasing their second property so long as they intend to promote their first residential property. Lower the LTV limit on housing loans granted by monetary establishments regulated by MAS from 70% to 60% for property purchasers who are individuals with a number of outstanding housing loans on the time of the brand new housing purchase. Singapore Property Measures - 30 August 2010 The most popular seek for the number of bedrooms in Singapore is 4, followed by 2 and three. Lush Acres EC @ Sengkang
Discover out more about real estate funding in the area, together with info on international funding incentives and property possession. Many Singaporeans have been investing in property across the causeway in recent years, attracted by comparatively low prices. However, those who need to exit their investments quickly are likely to face significant challenges when trying to sell their property – and could finally be stuck with a property they can't sell. Career improvement programmes, in-house valuation, auctions and administrative help, venture advertising and marketing, skilled talks and traisning are continuously planned for the sales associates to help them obtain better outcomes for his or her shoppers while at Knight Frank Singapore. No change Present Rules
Extending the tax exemption would help. The exemption, which may be as a lot as $2 million per family, covers individuals who negotiate a principal reduction on their existing mortgage, sell their house short (i.e., for lower than the excellent loans), or take part in a foreclosure course of. An extension of theexemption would seem like a common-sense means to assist stabilize the housing market, but the political turmoil around the fiscal-cliff negotiations means widespread sense could not win out. Home Minority Chief Nancy Pelosi (D-Calif.) believes that the mortgage relief provision will be on the table during the grand-cut price talks, in response to communications director Nadeam Elshami. Buying or promoting of blue mild bulbs is unlawful.
A vendor's stamp duty has been launched on industrial property for the primary time, at rates ranging from 5 per cent to 15 per cent. The Authorities might be trying to reassure the market that they aren't in opposition to foreigners and PRs investing in Singapore's property market. They imposed these measures because of extenuating components available in the market." The sale of new dual-key EC models will even be restricted to multi-generational households only. The models have two separate entrances, permitting grandparents, for example, to dwell separately. The vendor's stamp obligation takes effect right this moment and applies to industrial property and plots which might be offered inside three years of the date of buy. JLL named Best Performing Property Brand for second year running
The data offered is for normal info purposes only and isn't supposed to be personalised investment or monetary advice. Motley Fool Singapore contributor Stanley Lim would not personal shares in any corporations talked about. Singapore private home costs increased by 1.eight% within the fourth quarter of 2012, up from 0.6% within the earlier quarter. Resale prices of government-built HDB residences which are usually bought by Singaporeans, elevated by 2.5%, quarter on quarter, the quickest acquire in five quarters. And industrial property, prices are actually double the levels of three years ago. No withholding tax in the event you sell your property. All your local information regarding vital HDB policies, condominium launches, land growth, commercial property and more
There are various methods to go about discovering the precise property. Some local newspapers (together with the Straits Instances ) have categorised property sections and many local property brokers have websites. Now there are some specifics to consider when buying a 'new launch' rental. Intended use of the unit Every sale begins with 10 p.c low cost for finish of season sale; changes to 20 % discount storewide; follows by additional reduction of fiftyand ends with last discount of 70 % or extra. Typically there is even a warehouse sale or transferring out sale with huge mark-down of costs for stock clearance. Deborah Regulation from Expat Realtor shares her property market update, plus prime rental residences and houses at the moment available to lease Esparina EC @ Sengkang - ↑ P.L. Tchebychev. Sur la fonction qui détermine la totalité des nombres premiers. Mémoires présentés à l'Académie Impériale des Sciences de St-Pétersbourg par divers savants, VI 1851, 141-157
- ↑ Leonhard Euler. Variae observationes circa series infinitas. Commentarii academiae scientiarum Petropolitanae 9 (1737), 160-188.
- ↑ Although this equivalence is not explicitly mentioned there,it can for instance be easily derived from the material in chapter I.3 of: G. Tenenbaum. Introduction to analytic and probabilistic number theory. Translated from the second French edition (1995) by C. B. Thomas. Cambridge Studies in Advanced Mathematics, 46. Cambridge University Press, Cambridge,1995.
Further reading
- Yaglom and Yaglom Challenging mathematical problems with elementary solutions Vol 2, problems 171, 173, 174
External links
I had like 17 domains hosted on single account, and never had any special troubles. If you are not happy with the service you will get your money back with in 45 days, that's guaranteed. But the Search Engine utility inside the Hostgator account furnished an instant score for my launched website. Fantastico is unable to install WordPress in a directory which already have any file i.e to install WordPress using Fantastico the destination directory must be empty and it should not have any previous installation files. When you share great information, others will take note. Once your hosting is purchased, you will need to setup your domain name to point to your hosting. Money Back: All accounts of Hostgator come with a 45 day money back guarantee. If you have any queries relating to where by and how to use Hostgator Discount Coupon, you can make contact with us at our site. If you are starting up a website or don't have too much website traffic coming your way, a shared plan is more than enough. Condition you want to take advantage of the worldwide web you prerequisite a HostGator web page, -1 of the most trusted and unfailing web suppliers on the world wide web today. Since, single server is shared by 700 to 800 websites, you cannot expect much speed.
Hostgator tutorials on how to install Wordpress need not be complicated, especially when you will be dealing with a web hosting service that is friendly for novice webmasters and a blogging platform that is as intuitive as riding a bike. After that you can get Hostgator to host your domain and use the wordpress to do the blogging. Once you start site flipping, trust me you will not be able to stop. I cut my webmaster teeth on Control Panel many years ago, but since had left for other hosting companies with more commercial (cough, cough) interfaces. If you don't like it, you can chalk it up to experience and go on. First, find a good starter template design. When I signed up, I did a search for current "HostGator codes" on the web, which enabled me to receive a one-word entry for a discount. Your posts, comments, and pictures will all be imported into your new WordPress blog.
I had like 17 domains hosted on single account, and never had any special troubles. If you are not happy with the service you will get your money back with in 45 days, that's guaranteed. But the Search Engine utility inside the Hostgator account furnished an instant score for my launched website. Fantastico is unable to install WordPress in a directory which already have any file i.e to install WordPress using Fantastico the destination directory must be empty and it should not have any previous installation files. When you share great information, others will take note. Once your hosting is purchased, you will need to setup your domain name to point to your hosting. Money Back: All accounts of Hostgator come with a 45 day money back guarantee. If you have any queries relating to where by and how to use Hostgator Discount Coupon, you can make contact with us at our site. If you are starting up a website or don't have too much website traffic coming your way, a shared plan is more than enough. Condition you want to take advantage of the worldwide web you prerequisite a HostGator web page, -1 of the most trusted and unfailing web suppliers on the world wide web today. Since, single server is shared by 700 to 800 websites, you cannot expect much speed.
Hostgator tutorials on how to install Wordpress need not be complicated, especially when you will be dealing with a web hosting service that is friendly for novice webmasters and a blogging platform that is as intuitive as riding a bike. After that you can get Hostgator to host your domain and use the wordpress to do the blogging. Once you start site flipping, trust me you will not be able to stop. I cut my webmaster teeth on Control Panel many years ago, but since had left for other hosting companies with more commercial (cough, cough) interfaces. If you don't like it, you can chalk it up to experience and go on. First, find a good starter template design. When I signed up, I did a search for current "HostGator codes" on the web, which enabled me to receive a one-word entry for a discount. Your posts, comments, and pictures will all be imported into your new WordPress blog.
I had like 17 domains hosted on single account, and never had any special troubles. If you are not happy with the service you will get your money back with in 45 days, that's guaranteed. But the Search Engine utility inside the Hostgator account furnished an instant score for my launched website. Fantastico is unable to install WordPress in a directory which already have any file i.e to install WordPress using Fantastico the destination directory must be empty and it should not have any previous installation files. When you share great information, others will take note. Once your hosting is purchased, you will need to setup your domain name to point to your hosting. Money Back: All accounts of Hostgator come with a 45 day money back guarantee. If you have any queries relating to where by and how to use Hostgator Discount Coupon, you can make contact with us at our site. If you are starting up a website or don't have too much website traffic coming your way, a shared plan is more than enough. Condition you want to take advantage of the worldwide web you prerequisite a HostGator web page, -1 of the most trusted and unfailing web suppliers on the world wide web today. Since, single server is shared by 700 to 800 websites, you cannot expect much speed.
Hostgator tutorials on how to install Wordpress need not be complicated, especially when you will be dealing with a web hosting service that is friendly for novice webmasters and a blogging platform that is as intuitive as riding a bike. After that you can get Hostgator to host your domain and use the wordpress to do the blogging. Once you start site flipping, trust me you will not be able to stop. I cut my webmaster teeth on Control Panel many years ago, but since had left for other hosting companies with more commercial (cough, cough) interfaces. If you don't like it, you can chalk it up to experience and go on. First, find a good starter template design. When I signed up, I did a search for current "HostGator codes" on the web, which enabled me to receive a one-word entry for a discount. Your posts, comments, and pictures will all be imported into your new WordPress blog.