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Simon Sidon
Simon Sidon or Simon Szidon (1892 in Versec, Kingdom of Hungary – 27 April 1941, Budapest, Hungary) was a reclusive Hungarian mathematician who worked on trigonometric series and orthogonal systems and who introduced Sidon sequences and Sidon sets. Death On 27 April 1941, Sidon died from pneumonia Pneumonia is an inflammatory condition of the lung primarily affecting the small air sacs known as alveoli. Symptoms typically include some combination of productive or dry cough, chest pain, fever, and difficulty breathing. The severity ... in the hospital after a ladder fell on him and broke his leg. References External links * 20th-century Hungarian mathematicians 1892 births 1941 deaths Austro-Hungarian mathematicians {{mathematician-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vršac
Vršac ( sr-cyr, Вршац, ; hu, Versec; ro, Vârșeț) is a List of cities in Serbia, city and the administrative centre of the South Banat District in the autonomous province of Vojvodina, Serbia. As of 2011, the city urban area had a population of 35,701, while the city administrative area had 52,026 inhabitants. It is located in the geographical region of Banat. Name The name ''Vršac'' is of Serbian language, Serbian origin, ultimately deriving from Proto-Slavic wikt:Reconstruction:Proto-Slavic/vьrxъ, *vьrxъ, meaning "summit" In Serbian, the city is known as Вршац or ''Vršac'', in Romanian language, Romanian as ''Vârșeț'', in Hungarian language, Hungarian as ''Versec'' or ''Versecz'', in German language, German as ''Werschetz'', and in Turkish language, Turkish as ''Virşac'' or ''Verşe''. History There are traces of human settlement from the paleolithic, Palaeolithic and Neolithic periods. Remains from two types of Neolithic cultures have been discovered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kingdom Of Hungary
The Kingdom of Hungary was a monarchy in Central Europe that existed for nearly a millennium, from the Middle Ages into the 20th century. The Principality of Hungary emerged as a Christian kingdom upon the coronation of the first king Stephen I at Esztergom around the year 1000;Kristó Gyula – Barta János – Gergely Jenő: Magyarország története előidőktől 2000-ig (History of Hungary from the prehistory to 2000), Pannonica Kiadó, Budapest, 2002, , p. 687, pp. 37, pp. 113 ("Magyarország a 12. század második felére jelentős európai tényezővé, középhatalommá vált."/"By the 12th century Hungary became an important European factor, became a middle power.", "A Nyugat részévé vált Magyarország.../Hungary became part of the West"), pp. 616–644 his family (the Árpád dynasty) led the monarchy for 300 years. By the 12th century, the kingdom became a European middle power within the Western world. Due to the Ottoman occupation of the central and south ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Budapest
Budapest (, ; ) is the capital and most populous city of Hungary. It is the ninth-largest city in the European Union by population within city limits and the second-largest city on the Danube river; the city has an estimated population of 1,752,286 over a land area of about . Budapest, which is both a city and county, forms the centre of the Budapest metropolitan area, which has an area of and a population of 3,303,786; it is a primate city, constituting 33% of the population of Hungary. The history of Budapest began when an early Celtic settlement transformed into the Roman town of Aquincum, the capital of Lower Pannonia. The Hungarians arrived in the territory in the late 9th century, but the area was pillaged by the Mongols in 1241–42. Re-established Buda became one of the centres of Renaissance humanist culture by the 15th century. The Battle of Mohács, in 1526, was followed by nearly 150 years of Ottoman rule. After the reconquest of Buda in 1686, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hungary
Hungary ( hu, Magyarország ) is a landlocked country in Central Europe. Spanning of the Carpathian Basin, it is bordered by Slovakia to the north, Ukraine to the northeast, Romania to the east and southeast, Serbia to the south, Croatia and Slovenia to the southwest, and Austria to the west. Hungary has a population of nearly 9 million, mostly ethnic Hungarians and a significant Romani minority. Hungarian, the official language, is the world's most widely spoken Uralic language and among the few non-Indo-European languages widely spoken in Europe. Budapest is the country's capital and largest city; other major urban areas include Debrecen, Szeged, Miskolc, Pécs, and Győr. The territory of present-day Hungary has for centuries been a crossroads for various peoples, including Celts, Romans, Germanic tribes, Huns, West Slavs and the Avars. The foundation of the Hungarian state was established in the late 9th century AD with the conquest of the Carpathian Basin by Hungar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sidon Sequence
In number theory, a Sidon sequence is a sequence A=\ of natural numbers in which all pairwise sums a_i+a_j (for i\le j) are different. Sidon sequences are also called Sidon sets; they are named after the Hungarian mathematician Simon Sidon, who introduced the concept in his investigations of Fourier series. The main problem in the study of Sidon sequences, posed by Sidon, is to find the maximum number of elements that a Sidon sequence can contain, up to some bound x. Despite a large body of research, the question remained unsolved. Early results Paul Erdős and Pál Turán proved that, for every x>0, the number of elements smaller than x in a Sidon sequence is at most \sqrt+O(\sqrt . Several years earlier, James Singer had constructed Sidon sequences with \sqrt(1-o(1)) terms less than ''x''. Infinite Sidon sequences Erdős also showed that, for any particular infinite Sidon sequence A with A(x) denoting the number of its elements up to x, \liminf_ \frac\leq 1. That is, infinit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sidon Set
In number theory, a Sidon sequence is a sequence A=\ of natural numbers in which all pairwise sums a_i+a_j (for i\le j) are different. Sidon sequences are also called Sidon sets; they are named after the Hungarian mathematician Simon Sidon, who introduced the concept in his investigations of Fourier series. The main problem in the study of Sidon sequences, posed by Sidon, is to find the maximum number of elements that a Sidon sequence can contain, up to some bound x. Despite a large body of research, the question remained unsolved. Early results Paul Erdős and Pál Turán proved that, for every x>0, the number of elements smaller than x in a Sidon sequence is at most \sqrt+O(\sqrt . Several years earlier, James Singer had constructed Sidon sequences with \sqrt(1-o(1)) terms less than ''x''. Infinite Sidon sequences Erdős also showed that, for any particular infinite Sidon sequence A with A(x) denoting the number of its elements up to x, \liminf_ \frac\leq 1. That is, infinite S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Springer-Verlag
Springer Science+Business Media, commonly known as Springer, is a German multinational publishing company of books, e-books and peer-reviewed journals in science, humanities, technical and medical (STM) publishing. Originally founded in 1842 in Berlin, it expanded internationally in the 1960s, and through mergers in the 1990s and a sale to venture capitalists it fused with Wolters Kluwer and eventually became part of Springer Nature in 2015. Springer has major offices in Berlin, Heidelberg, Dordrecht, and New York City. History Julius Springer founded Springer-Verlag in Berlin in 1842 and his son Ferdinand Springer grew it from a small firm of 4 employees into Germany's then second largest academic publisher with 65 staff in 1872.Chronology ". Springer Science+Business Media. In 1964, Springer expanded its business internationally, o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pneumonia
Pneumonia is an inflammatory condition of the lung primarily affecting the small air sacs known as alveoli. Symptoms typically include some combination of productive or dry cough, chest pain, fever, and difficulty breathing. The severity of the condition is variable. Pneumonia is usually caused by infection with viruses or bacteria, and less commonly by other microorganisms. Identifying the responsible pathogen can be difficult. Diagnosis is often based on symptoms and physical examination. Chest X-rays, blood tests, and culture of the sputum may help confirm the diagnosis. The disease may be classified by where it was acquired, such as community- or hospital-acquired or healthcare-associated pneumonia. Risk factors for pneumonia include cystic fibrosis, chronic obstructive pulmonary disease (COPD), sickle cell disease, asthma, diabetes, heart failure, a history of smoking, a poor ability to cough (such as following a stroke), and a weak immune system. Vaccines to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A Portrait Of Paul Erdős
A, or a, is the first letter and the first vowel of the Latin alphabet, used in the modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is ''a'' (pronounced ), plural ''aes''. It is similar in shape to the Ancient Greek letter alpha, from which it derives. The uppercase version consists of the two slanting sides of a triangle, crossed in the middle by a horizontal bar. The lowercase version can be written in two forms: the double-storey a and single-storey ɑ. The latter is commonly used in handwriting and fonts based on it, especially fonts intended to be read by children, and is also found in italic type. In English grammar, " a", and its variant " an", are indefinite articles. History The earliest certain ancestor of "A" is aleph (also written 'aleph), the first letter of the Phoenician alphabet, which consisted entirely of consonants (for that reason, it is also called an abjad to distinguish it fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1892 Births
Year 189 ( CLXXXIX) was a common year starting on Wednesday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Silanus and Silanus (or, less frequently, year 942 ''Ab urbe condita''). The denomination 189 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years. Events By place Roman Empire * Plague (possibly smallpox) kills as many as 2,000 people per day in Rome. Farmers are unable to harvest their crops, and food shortages bring riots in the city. China * Liu Bian succeeds Emperor Ling, as Chinese emperor of the Han Dynasty. * Dong Zhuo has Liu Bian deposed, and installs Emperor Xian as emperor. * Two thousand eunuchs in the palace are slaughtered in a violent purge in Luoyang, the capital of Han. By topic Arts and sciences * Galen publishes his ''"Treatise on the various temperaments"'' (aka ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1941 Deaths
Events Below, the events of World War II have the "WWII" prefix. January * January–August – 10,072 men, women and children with mental and physical disabilities are asphyxiated with carbon monoxide in a gas chamber, at Hadamar Euthanasia Centre in Germany, in the first phase of mass killings under the Action T4 program here. * January 1 – Thailand's Prime Minister Plaek Phibunsongkhram decrees January 1 as the official start of the Thai solar calendar new year (thus the previous year that began April 1 had only 9 months). * January 3 – A decree (''Normalschrifterlass'') promulgated in Germany by Martin Bormann, on behalf of Adolf Hitler, requires replacement of blackletter typefaces by Antiqua. * January 4 – The short subject ''Elmer's Pet Rabbit'' is released, marking the second appearance of Bugs Bunny, and also the first to have his name on a title card. * January 5 – WWII: Battle of Bardia in Libya: Australian and British troops de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
