| Thomas_R__Nicely Includes twin prime counts, tables of first occurrence prime gaps, papers. |
| The_Time_Traveler A group with new propositions in various areas of number theory. |
| Visualizing_the_Distribution_of_Prime_Numbers Investigation into patterns in the distribution of the primes by visualizing them. |
| Wikipedia__Prime_Numbers Index to many prime-related articles. |
| World_of_Numbers__World_of_Palindromic_Primes Records, statistics, curios and puzzles about primes reading the same backwards. Compiled by Patrick De Geest. |
| Bipeds_and_Prime_Numbers Graduation address by former professor of philosophy Garrett Barden. Mentions primes as sign of human curiosity. (September 18, 2001) |
| Chair_of_General_Chemistry,_Altai_State_Technical_University Describes scientific work and educational programs, lists group publications. |
| Department_of_Chemistry Contains online course material and lists faculty members. |
| Earth_Measurement_Corp_ Near-surface geophysical data acquisition, processing and interpretation. |
| Electro-Seise,_Inc_ 3D airborne micro gravity/E surveys for subsurface hydrocarbons. |
| Fairfield_Industries_Incorporated Fairfield is a geophysical company known for its development and use of advanced technology for acquisition and processing, and its licensing of seismic data. |
| G_A__Ryzhikov_and_M_S__Biryulina,_Consultants Special processing for traditional marine data using "Partial Synergetic Imaging-", or PSI-criterion. |
| Getech Geophysical contractor providing gravity and magnetic services and products to the international oil and mining industry. Offices in Leeds and Houston. |
| Gibson_Consulting Interpretation of gravity & magnetics for hydrocarbon exploration. |
| Input_Output,_Inc_ Provider of land, marine and reservoir seismic instrumentation. Includes comprehensive data sheets. |
| Interactive_Interpretation_&_Training,_Inc_ Outsourcing geoscience for the upstream petroleum industry: geophysics, geology, petroleum engineering, geochemistry, workstation rental. Landmark and GeoQuest software. |
| JGI,_Inc_ Acquisition of seismic and other geophysical data, geothermal surveys and remote sensing. Japan based. |
| Meridian_Surveys Survey and geophysical consultants to the oil and gas industry. |
| Montason_Exploration_Inc_ Geophysical acquisition, processing and interpretation. Electromagnetic technology produces virtual subsurface conductivity log. |
| Oilsearch_Plc_-_Airborne_Geophysical_Oil_Survey_Company Airborne geophysical oil survey company specialising in remote fluorescence sensing and magnetic data recovery. |
| PGS_Geophysical Onshore and marine seismic acquisition and analysis. Reservoir imaging, characterization and monitoring. Multiclient 3D data library. |
| Reid_Geophysics Offering gravity and magnetic survey specification, processing and interpretation. Proprietary software. |
| RGR__Method_of_Effective_Specular_Points A novel approach to Reflector Geometry Reconstruction: proper assimilation of prestacked multioffset traveltimes, macro-model-independent seismic reflection (depth) imaging. |
| Seismic_Consultants_Group_Pty__Ltd_ Seismic Consultants Group (SCG) provides personnel for field supervision and quality control of geophysical surveys to the oil and gas exploration industry worldwide |
| Seismic_Imaging_Research Research reports on subsalt imaging, depth migration, velocity model building, seismic modeling, converted mode energy and overpressure prediction. |
| SeismicDocs Online professional geophysical consulting service. |
| Seismograph_Rental_,_seismic_tomography_services Passive seismic tomography services for oil exploration. Seismograph and vibroseis rental. Pipeline pollution early warning systems. Seismological investigations. Crosshole seismic tomography. |
| Seistronix_RAS-24_Exploration_Seismograph Seistronix manufactures, leases and sells exploration seismographs and related geophysical equipment for oil, gas, mineral and general geotechnical exploration using seismic refraction, 2D and 3D seis |
| Sharp_Deconvolution_in_P-tau_Domain Elimination of intrabed multiples: SoSI-inversion. Site shows a novel approach to the comprehensive elimination of multiples -including intrabed ones. It is based on recursive representation of Born s |
| Signature_Seismic_Processing_Inc_ 2D and 3D seismic data processing services for both land and marine datasets. |
| Society_of_Exploration_Geophysicists Home page of the SEG, which hosts 2 monthly publications- The Leading Edge and the SEG Journal, and yearly trade shows, at the international, national, and regional level. The major organization for g |
| Sources_of_Seismic_Interpretation_Error Powerpoint presentations illustrating common reasons for interpretation error. Free viewer available from site. |
| Sperling_Geophysics Seismic data acquisition, interpretation and modeling, including prospect evaluation. |
| Topaz_Energy_Exploration_Ltd_ Geochemically-based surface exploration for hydrocarbons using magnetic horizontal gradient and radiometric surveys |
| A4_Scientific,_Inc_ Small business offering analyses of volatiles, semi-volatiles, metals, pesticides, herbicides and explosives. Lists facilities, analytes, and includes chain of custody form, and contacts in The Woodla |
| AAC_Trinity_Inc_ Article on sediment sample collection, methanol preservation for volatile analysis, and details of services, including industrial hygiene at NELAC accredited laboratory in Farmington Hills, MI. |
| Accurate_Labs An environmental laboratory primarily serving municipal and industrial clients in Oklahoma, Texas, and Kansas. Provides analytical support for all projects involving waste water, drinking water, groun |
| Accutest Environmental analytical and testing services. Based in New Jersey. |
| ACZ_Laboratories,_Inc_ Offer state compliant analytical testing, for inorganic and organic contaminants, such as mine and surface water quality and mercury in biota tissue. Details of organization and techniques range, with |
| Air_Toxics_Ltd_ California facility specializing in analysis of environmental air samples, including ambient air, source emissions, soil and landfill gas, and indoor air, for federal, state and private industrial pro |
![[An image of some prime numbers]](http://odin.mdacc.tmc.edu/~krc/numbers/prime.html/prim.gif)
Mathematicians have a special fondness for definitions. Theobjects they study often have no physical presence: you can't touchthem, weigh them, or smell them. So, precise definitions are used toprovide a solid underpinning to their subject. Definitions are madefor two reasons. Sometimes a mathematician makes a definition inorder to have a simple shorthand term for a more complicated objectthat was needed to make sense of a proof. In other cases, adefinition is a kind of generalization, made to unite lots of examplesand special cases into a single kind of thing deserving further study.In the present document, we want to investigate some of theconsequences of a single, simple definition of the latter kind.Definition: An integer p is called aprime number if the only positive integers that divide p are 1 andp itself. Integers that are not prime are calledcomposite. Here are the first few prime numbers: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, ... Prime numbers are special because they are the elementary buildingblocks of the multiplicative structure on the integers; every integercan be written in only one way as a product of its prime factors. Themathematically precise version of this assertion is known as the The Fundamental Theorem of Arithmetic. There are a number of interesting questions you can ask aboutprime numbers and factorizations. Given any integer n, how do you find its primefactorization? Given any integer n, how do you decide if it is aprime number? How many prime numbers are there? Can youlist all the prime numbers less than a given bound?[Home Page][Bioinformatics][Mathematics][Creative Efforts][HOME][PREVIOUS][NEXT][UP][DOWN]Disclaimer:This page was last updated on 12 October 2002. It is entirely possiblethat the information contained herein no longer has any connectionwith reality (assuming it ever did). Feel free to sendconstructive comments orinane criticisms to:Kevin R. CoombesDepartment of BiostatisticsUniversity of Texas M.D.Anderson Cancer Center1515 Holcombe Blvd., Box 447Houston, TX 77030