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70000 (number)
70,000 (seventy thousand) is the natural number that comes after 69,999 and before 70,001. It is a round number. Selected numbers in the range 70001–79999 70001 to 70999 71000 to 71999 * 71656 = pentagonal pyramidal number 72000 to 72999 73000 to 73999 * 73296 = is the smallest number ''n'', for which ''n''−3, ''n''−2, ''n''−1, ''n''+1, ''n''+2, ''n''+3 are all Sphenic number. * 73440 = 15 × 16 × 17 × 18 * 73712 = number of ''n''-Queens Problem solutions for ''n'' = 13 * 73728 = 3- smooth number 74000 to 74999 * 74088 = 423 * 74205 = registry number of the USS Defiant on ''Star Trek: Deep Space Nine'' * 74353 = Friedman prime * 74656 = registry number of the USS Voyager on '' Star Trek: Voyager'' * 74897 = Friedman prime 75000 to 75999 * 75025 = Fibonacci number, Markov number * 75361 = Carmichael number 76000 to 76999 * 76084 = amicable number with 63020 * 76424 = tetranacci number 77000 to 77999 * 77777 = repdigit * 77778 = Kaprekar number 78000 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Number
In mathematics, the natural numbers are those numbers used for counting (as in "there are ''six'' coins on the table") and ordering (as in "this is the ''third'' largest city in the country"). Numbers used for counting are called ''Cardinal number, cardinal numbers'', and numbers used for ordering are called ''Ordinal number, ordinal numbers''. Natural numbers are sometimes used as labels, known as ''nominal numbers'', having none of the properties of numbers in a mathematical sense (e.g. sports Number (sports), jersey numbers). Some definitions, including the standard ISO/IEC 80000, ISO 80000-2, begin the natural numbers with , corresponding to the non-negative integers , whereas others start with , corresponding to the positive integers Texts that exclude zero from the natural numbers sometimes refer to the natural numbers together with zero as the whole numbers, while in other writings, that term is used instead for the integers (including negative integers). The natural ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
60,000
60,000 (sixty thousand) is the natural number that comes after 59,999 and before 60,001. It is a round number. It is the value of \varphi( F25). Selected numbers in the range 60,000–69,999 60,001 to 60,999 * 60,049 = Leyland number * 60,101 = smallest prime with period of reciprocal 100 61,000 to 61,999 62,000 to 62,999 * 62,208 = 3- smooth number * 62,210 = Markov number * 62,745 = Carmichael number 63,000 to 63,999 * 63,020 = amicable number with 76084 * 63,360 = inches in a mile * 63,600 = number of free 12-ominoes * 63,750 = pentagonal pyramidal number * 63,973 = Carmichael number 64,000 to 64,999 * 64,000 = 403; also 64,000 Dollar Question * 64,009 = sum of the cubes of the first 22 positive integers * 64,079 = Lucas number * 64,442 = Number of integer degree intersections on Earth: 360 longitudes * 179 latitudes + 2 poles = 64442. 65,000 to 65,999 * 65,025 = 2552, palindromic in base 11 (4494411) * 65,279 = Unicode code point for byte order mark * 65,534 = U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphenic Number
In number theory, a sphenic number (from grc, σφήνα, 'wedge') is a positive integer that is the product of three distinct prime numbers. Because there are infinitely many prime numbers, there are also infinitely many sphenic numbers. Definition A sphenic number is a product ''pqr'' where ''p'', ''q'', and ''r'' are three distinct prime numbers. In other words, the sphenic numbers are the square-free 3-almost primes. Examples The smallest sphenic number is 30 = 2 × 3 × 5, the product of the smallest three primes. The first few sphenic numbers are : 30, 42, 66, 70, 78, 102, 105, 110, 114, 130, 138, 154, 165, ... the largest known sphenic number is :(282,589,933 − 1) × (277,232,917 − 1) × (274,207,281 − 1). It is the product of the three largest known primes. Divisors All sphenic numbers have exactly eight divisors. If we express the sphenic number as n = p \cdot q \cdot r, where ''p'', ''q'', and ''r'' are distinct primes, then the set of divisors of ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eight Queens Puzzle
The eight queens puzzle is the problem of placing eight chess queens on an 8×8 chessboard so that no two queens threaten each other; thus, a solution requires that no two queens share the same row, column, or diagonal. There are 92 solutions. The problem was first posed in the mid-19th century. In the modern era, it is often used as an example problem for various computer programming techniques. The eight queens puzzle is a special case of the more general ''n'' queens problem of placing ''n'' non-attacking queens on an ''n''×''n'' chessboard. Solutions exist for all natural numbers ''n'' with the exception of ''n'' = 2 and ''n'' = 3. Although the exact number of solutions is only known for ''n'' ≤ 27, the asymptotic growth rate of the number of solutions is (0.143 ''n'')''n''. History Chess composer Max Bezzel published the eight queens puzzle in 1848. Franz Nauck published the first solutions in 1850.W. W. Rouse Ball (1960) "The Eight Queens Problem", in ''Mathema ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smooth Number
In number theory, an ''n''-smooth (or ''n''-friable) number is an integer whose prime factors are all less than or equal to ''n''. For example, a 7-smooth number is a number whose every prime factor is at most 7, so 49 = 72 and 15750 = 2 × 32 × 53 × 7 are both 7-smooth, while 11 and 702 = 2 × 33 × 13 are not 7-smooth. The term seems to have been coined by Leonard Adleman. Smooth numbers are especially important in cryptography, which relies on factorization of integers. The 2-smooth numbers are just the powers of 2, while 5-smooth numbers are known as regular numbers. Definition A positive integer is called B-smooth if none of its prime factors are greater than B. For example, 1,620 has prime factorization 22 × 34 × 5; therefore 1,620 is 5-smooth because none of its prime factors are greater than 5. This definition includes numbers that lack some of the smaller prime factors; for example, both 10 and 12 are 5-smooth, even though they miss out the prime factors 3 and 5, resp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deep Space Nine
''Star Trek: Deep Space Nine'' (abbreviated as ''DS9'') is an American science fiction television series created by Rick Berman and Michael Piller. The fourth series in the ''Star Trek'' media franchise, it originally aired in syndication from January 3, 1993, to June 2, 1999, spanning 176 episodes over seven seasons. Set in the 24th century, when Earth is part of a United Federation of Planets, its narrative is centered on the eponymous space station Deep Space Nine, located adjacent to a wormhole connecting Federation territory to the Gamma Quadrant on the far side of the Milky Way galaxy. Following the success of '' Star Trek: The Next Generation'', Paramount Pictures commissioned a new series set in the ''Star Trek'' fictional universe. In creating ''Deep Space Nine'', Berman and Piller drew upon plot elements introduced in ''The Next Generation'', namely the conflict between two alien species, the Cardassians and the Bajorans. ''Deep Space Nine'' was the first ''Star Tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Voyager
Voyager may refer to: Science and Astronomy * Voyager 1 – a space probe launched by NASA September 5, 1977 as part of the Voyager program. * Voyager 2 – a space probe launched by NASA on August 20, 1977. Computing and communications * LG Voyager, a mobile phone model manufactured by LG Electronics * NCR Voyager, a computer platform produced by NCR Corporation * Voyager (computer worm), a computer worm affecting Oracle databases * Voyager (library program), the integrated library system from Ex Libris Group * Voyager (web browser), a web browser for Amiga computers * HP Voyager series, code name for the Hewlett-Packard series of handheld programmable calculators including the HP-10C/11C/12C/15C/16C Transport Air * Airbus Voyager, Royal Air Force version of the Airbus A330 MRTT * Frequent flyer program of South African Airways * Egvoyager Voyager 203, an Italian ultralight aircraft * Raj Hamsa Voyager, an Indian ultralight trike design * Rutan Voyager, the first airpla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sierpiński Number
In number theory, a Sierpiński number is an odd natural number ''k'' such that k \times 2^n + 1 is composite for all natural numbers ''n''. In 1960, Wacław Sierpiński proved that there are infinitely many odd integers ''k'' which have this property. In other words, when ''k'' is a Sierpiński number, all members of the following set are composite: :\left\. If the form is instead k \times 2^n - 1 , then ''k'' is a Riesel number. Known Sierpiński numbers The sequence of currently ''known'' Sierpiński numbers begins with: : 78557, 271129, 271577, 322523, 327739, 482719, 575041, 603713, 903983, 934909, 965431, 1259779, 1290677, 1518781, 1624097, 1639459, 1777613, 2131043, 2131099, 2191531, 2510177, 2541601, 2576089, 2931767, 2931991, ... . The number 78557 was proved to be a Sierpiński number by John Selfridge in 1962, who showed that all numbers of the form have a factor in the covering set . For another known Sierpiński number, 271129, the covering set is . Most current ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
