The fundamental theorem of arithmetic states that every positive integer can be written as a product of primes in a unique way, though the way the prime numbers occur is a difficult problem for mathematicians. When a number is larger, it is more difficult to know if it is a prime number. One of the answers is the prime number theorem. One of the unsolved problems is Goldbach's conjecture.
There is a simple method to find a list of prime numbers. Eratosthenes created it. It has the name Sieve of Eratosthenes. It catches numbers that are not prime (like a sieve), and lets the prime numbers pass through.
The method works with a list of numbers, and a special number called "b" that changes during the method. As one goes through the method, they circle some numbers in the list and cross out others. Each circled number is prime and each crossed-out number is composite. At the start, all the numbers are plain: not circled and not crossed out.
The method is always the same:
For example, one could carry out this method on a list of the numbers from 2 to 10. At the end, the numbers 2, 3, 5, and 7 will end up circled. These are prime numbers. The numbers 4, 6, 8, 9 and 10 will be crossed out. These are composite numbers.
This method or algorithm takes too long to find very large prime numbers. However, it is less complicated than methods used for very large primes, such as Fermat's primality test (a test to see whether a number is prime or not) and the Miller-Rabin primality test.
Prime numbers are very important in mathematics and computer science. Very long numbers are hard to solve. It is difficult to find their prime factors, so most of the time, numbers that are probably prime are used for encryption and secret codes. For example:
Igloo
An igloo (or iglu) is a shelter (a place for people to stay warm and dry) made from blocks of snow placed on top of each other, often in the shape of a dome (like half of a hollow ball). They were used in winter as temporary shelters by hunters when they were away from their regular homes.
They were most often built in places where a lot of snow covers the land for weeks or months at a time, such as the far north of Canada and Greenland. Most igloos are built by native Inuit people (sometimes called "Eskimoes"). As they learned to build them better, sometimes people would build larger igloos that would last longer and hold more people, even for dancing.
Dust (disambiguation)
Dust is fine, solid particles of matter.
Dust may also mean:
For articles on how the word "dust" is used as a technical term in physics, astronomy, cosmology, and
environmental science, see:
The Phantom of the Opera
The Phantom of the Opera () is a French novel by Gaston Leroux. It was published in 1910. An English edition came out a year later.
The book was adapted to a musical by Andrew Lloyd Webber in 1986. The musical was made into a movie in 2004.
Movie versions include one starring Lon Chaney in 1925, one from 1943 with Claude Rains, another from 1962 with Herbert Lom, and "The Phantom of the Paradise" (1974). The story has been adapted to made for television movies several times.
The band iron maiden made a song name the phanTom of the Opera from their self titled album iron maiden.
Fleet, Hampshire
Fleet is a town in Hampshire, United Kingdom and tends to be a dormitory town serving London and Reading.
Fleet has one shopping center, and a music shop just off the High Street and many small, fun attractions.
There are a number of pubs there with some character, and even two small nightclubs. It has a lot of green, and is good for rambling but there is the danger of a field being an army firing range.
Its local business parks seem to be a focus for many CAD companies serving the local military in Fleet, Aldershot, and Farnborough. Notably there are AutoDesk and PTC.
There are also many good schools especially Heatherside Infant and Juniors and Court Moor!
It has its own train station on the London-Basingstoke line. It also has bus services running to and from local towns, including Reading. The local bus company did go bust a few times, notably at the same time as the major plague of train accidents and strikes in early 2002 - where combined with large snow deposits, made travel in or out of the town impossible or at least very unpleasant. Anyone who lived on the London-Basingstoke line will remember people being crammed into the guard-vans of the train after waiting 90 minutes, or being stuck between stations for what seemed like days.
Hentai
Hentai is a Japanese word that literally means "strange appearance", but also means "perverted". Hentai, because of this, is a word used by countries outside of Japan to show porn and sex-related anime, manga and video games. The word is not used to mean this in Japan. In Japan, terms such as "ecchi" are used.
The word hentai is sometimes used to apply to cartoon characters that are not anime characters. Hentai is the anime version of porn. There is on screen sex, often very graphic and very imaginative. Since hentai is anime, the performers are not bound by physical laws. Makers of hentai often use this in very creative ways. Some of the acts performed in hentai would be physically impossible. Some of the performers are often impossible themselves. Fairies, monsters, and even new and strange creatures are stars of hentai. Monsters and demons with tentacles are seen so often that “tentacle porn” is its own sub-category of hentai.
Most of the hentai (anime)-films in the late 1990s to the present day are based on Ero-Games, where the only actual goal is to date the girls in the game and have sex with one of them. The games feature various character-types, like a bookworm, a tough girl, a younger girl, and a tomboy. Ero-games can include highly taboo themes, such as coprophilia or dismemberment, pedophilia, and rape. Sometimes slightly less taboo subjects, such as incest. Some examples of these kind of game-to-hentai-anime conversions are Immoral Sisters, Isaku, Pia Carrot, Five Card, Bible Black, Words Worth, Night Shift Nurses, Huniepop, and Milk Junkies.
Famous hentai films include:
Rapping
Rapping is a type of vocals, like singing. It is different to singing because it is more like talking, but timed with rhythm over music. Someone who raps is called a rapper, or sometimes an MC. That stands for Master of Ceremonies.
Rapping can be done over music of many types (or genres), including jazz, house, reggae and many more. One genre of music that includes a lot of rapping is hip hop. What people think of as rapping today, was started by African Americans in New York City, USA, in the 1970s. People would talk over disco music DJs at parties, and this gradually evolved into rapping. But, the start of the art of rapping is even older. Reggae artists in Jamaica used a similar style to rapping from the 1950s. Going back further than that, the West African Griots (travelling musicians and poets) would also rap over tribal drums in the 1400s.
Today rapping is a very popular style of vocals. Many of the best selling artists in the world use it in their music.
Snowboarding
Snowboarding is a sport that is much like skiing. A person stands on a snowboard and rides down a mountain covered with snow. A snowboard is a flat board with bindings that hold your feet in place while gliding down the mountain. It is different from skiing because both feet are on one board - like surfing.
Some snowboarders like to ride over jumps and do tricks.
The snowboard was born in the seventy's through the imagination of several different Americans.
The original idea was born in 1965 through Sherman Poppen. He invented the ‘’snurfer ‘’, which was made of two skis fixed together, as a gift to his daughter. It soon became very popular, so he licensed it to the Brunswick Corporation who sold about a million over the next 10 years.