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Lychrel Number
A Lychrel number is a natural number that cannot form a palindrome through the iterative process of repeatedly reversing its digits and adding the resulting numbers. This process is sometimes called the ''196-algorithm'', after the most famous number associated with the process. In base ten, no Lychrel numbers have been yet proven to exist, but many, including 196, are suspected on heuristic and statistical grounds. The name "Lychrel" was coined by Wade Van Landingham as a rough anagram of "Cheryl", his girlfriend's first name. Reverse-and-add process The reverse-and-add process produces the sum of a number and the number formed by reversing the order of its digits. For example, 56 + 65 = 121. As another example, 125 + 521 = 646. Some numbers become palindromes quickly after repeated reversal and addition, and are therefore not Lychrel numbers. All one-digit and two-digit numbers eventually become palindromes after repeated reversal and addition. About 80% of all numbers under ... [...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 numbers'', and numbers used for ordering are called '' 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 jersey numbers). Some definitions, including the standard 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 numbers form a set. Many other number sets are built by succ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Binary Number
A binary number is a number expressed in the base-2 numeral system or binary numeral system, a method of mathematical expression which uses only two symbols: typically "0" ( zero) and "1" (one). The base-2 numeral system is a positional notation with a radix of 2. Each digit is referred to as a bit, or binary digit. Because of its straightforward implementation in digital electronic circuitry using logic gates, the binary system is used by almost all modern computers and computer-based devices, as a preferred system of use, over various other human techniques of communication, because of the simplicity of the language and the noise immunity in physical implementation. History The modern binary number system was studied in Europe in the 16th and 17th centuries by Thomas Harriot, Juan Caramuel y Lobkowitz, and Gottfried Leibniz. However, systems related to binary numbers have appeared earlier in multiple cultures including ancient Egypt, China, and India. Leibniz was speci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ahoy!
''Ahoy!'' was a computer magazine published between January 1984 and January 1989 in the US, focusing on all Commodore color computers, but especially the Commodore 64 and Amiga. History The first issue of ''Ahoy!'' was published in January 1984. The magazine was published monthly by Ion International and was headquartered in New York City. It published many games in BASIC and machine language, occasionally also printing assembly language source code. ''Ahoy!'' published a checksum A checksum is a small-sized block of data derived from another block of digital data for the purpose of detecting errors that may have been introduced during its transmission or storage. By themselves, checksums are often used to verify dat ... program called ''Flankspeed'' for entering machine language listings. ''Ahoy!'s AmigaUser'' was a related but separate publication dedicated to the Amiga. It was spun off from a series of columns in ''Ahoy!'' with the same title, and the first two is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transactor Publishing
''The Transactor'' was a computer magazine directed at users of Commodore home computers. In contrast to other Commodore-focused publications such as '' Commodore Magazine'' and ''COMPUTE!'s Gazette'', ''The Transactor'''s popularity was based on its coverage of deep technical issues and hardware hacking. ''INFO'' called ''The Transactor'' "the undeniable authority" on "Commodore programming and hardware information". Publication history The magazine was launched on 30 April 1978 as the official international bulletin of Commodore Canada to PET user groups. The early issues were low-tech mimeographed productions with no non-Commodore advertising and a roughly monthly release schedule. Despite its association with Commodore, the magazine earned a reputation for being honest and upfront about bugs and faults in Commodore's products. In September 1982 the magazine was relaunched as a fully independent, bimonthly, advertiser-supported publication. From this point the magazine be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jim Butterfield
Frank James "Jim" Butterfield (14 February 1936 – 29 June 2007), was a Toronto-based computer programmer, author, and television personality known for his work with early microcomputers. He is particularly noted for associations with Commodore Business Machines and the Toronto PET Users Group, for many books and articles on machine language programming, and for educational videos and TV programs. Early life and career Jim Butterfield was born on 14 February 1936 in Ponoka, Alberta, which is south of Edmonton. He was the third of four children to James and Nancy Butterfield, who had emigrated from England to farm. In 1953 he won a French scholarship to the Banff School of Fine Arts. He later attended the University of Alberta and the University of British Columbia but dropped out due to lack of interest. One of his first jobs was radio continuity writing in Alberta. In 1957, Butterfield began working for Canadian National/Canadian Pacific Telecommunications, at first as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microcomputer
A microcomputer is a small, relatively inexpensive computer having a central processing unit (CPU) made out of a microprocessor. The computer also includes memory and input/output (I/O) circuitry together mounted on a printed circuit board (PCB). Microcomputers became popular in the 1970s and 1980s with the advent of increasingly powerful microprocessors. The predecessors to these computers, mainframes and minicomputers, were comparatively much larger and more expensive (though indeed present-day mainframes such as the IBM System z machines use one or more custom microprocessors as their CPUs). Many microcomputers (when equipped with a keyboard and screen for input and output) are also personal computers (in the generic sense). An early use of the term ''personal computer'' in 1962 predates microprocessor-based designs. ''(See "Personal Computer: Computers at Companies" reference below)''. A ''microcomputer'' used as an embedded control system may have no human-readable i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base-10
The decimal numeral system (also called the base-ten positional numeral system and denary or decanary) is the standard system for denoting integer and non-integer numbers. It is the extension to non-integer numbers of the Hindu–Arabic numeral system. The way of denoting numbers in the decimal system is often referred to as ''decimal notation''. A ''decimal numeral'' (also often just ''decimal'' or, less correctly, ''decimal number''), refers generally to the notation of a number in the decimal numeral system. Decimals may sometimes be identified by a decimal separator (usually "." or "," as in or ). ''Decimal'' may also refer specifically to the digits after the decimal separator, such as in " is the approximation of to ''two decimals''". Zero-digits after a decimal separator serve the purpose of signifying the precision of a value. The numbers that may be represented in the decimal system are the decimal fractions. That is, fractions of the form , where is an integer, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Koji Yamashita , a fungus used in East Asian fermentation
{{disambiguation ...
Koji, Kōji, Kohji or Kouji may refer to: *Kōji (given name), a masculine Japanese given name *Kōji (Heian period) (康治), Japanese era, 1142–1144 *Kōji (Muromachi period) (弘治), Japanese era, 1555–1558 *Koji orange, a Japanese citrus cultivar *Andrew Koji Shiraki (born 1987), singer/songwriter known as ''Koji'' *Koji, the software that builds RPM packages for the Fedora project *''Koji'', the common name of the fungus ''Aspergillus oryzae'' *Koji, an interactive content creation tool from GoMeta See also *Kojii, music project by Kojii Helnwein *''Coji-Coji'' (コジコジ), an anime series sometimes romanized ''Koji Koji'' *Kōji mold Aspergillus oryzae ''Aspergillus oryzae'', also known as , is a filamentous fungus (a mold) used in East Asia to saccharify rice, sweet potato, and barley in the making of alcoholic beverages such as '' sake'' and ''shōchū'', and also to ferment soybeans f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subset
In mathematics, set ''A'' is a subset of a set ''B'' if all elements of ''A'' are also elements of ''B''; ''B'' is then a superset of ''A''. It is possible for ''A'' and ''B'' to be equal; if they are unequal, then ''A'' is a proper subset of ''B''. The relationship of one set being a subset of another is called inclusion (or sometimes containment). ''A'' is a subset of ''B'' may also be expressed as ''B'' includes (or contains) ''A'' or ''A'' is included (or contained) in ''B''. A ''k''-subset is a subset with ''k'' elements. The subset relation defines a partial order on sets. In fact, the subsets of a given set form a Boolean algebra under the subset relation, in which the join and meet are given by intersection and union, and the subset relation itself is the Boolean inclusion relation. Definition If ''A'' and ''B'' are sets and every element of ''A'' is also an element of ''B'', then: :*''A'' is a subset of ''B'', denoted by A \subseteq B, or equivalently, :* ''B'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sequence
In mathematics, a sequence is an enumerated collection of objects in which repetitions are allowed and order matters. Like a set, it contains members (also called ''elements'', or ''terms''). The number of elements (possibly infinite) is called the ''length'' of the sequence. Unlike a set, the same elements can appear multiple times at different positions in a sequence, and unlike a set, the order does matter. Formally, a sequence can be defined as a function from natural numbers (the positions of elements in the sequence) to the elements at each position. The notion of a sequence can be generalized to an indexed family, defined as a function from an ''arbitrary'' index set. For example, (M, A, R, Y) is a sequence of letters with the letter 'M' first and 'Y' last. This sequence differs from (A, R, M, Y). Also, the sequence (1, 1, 2, 3, 5, 8), which contains the number 1 at two different positions, is a valid sequence. Sequences can be '' finite'', as in these examples, or '' i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algorithm
In mathematics and computer science, an algorithm () is a finite sequence of rigorous instructions, typically used to solve a class of specific problems or to perform a computation. Algorithms are used as specifications for performing calculations and data processing. More advanced algorithms can perform automated deductions (referred to as automated reasoning) and use mathematical and logical tests to divert the code execution through various routes (referred to as automated decision-making). Using human characteristics as descriptors of machines in metaphorical ways was already practiced by Alan Turing with terms such as "memory", "search" and "stimulus". In contrast, a heuristic is an approach to problem solving that may not be fully specified or may not guarantee correct or optimal results, especially in problem domains where there is no well-defined correct or optimal result. As an effective method, an algorithm can be expressed within a finite amount of spac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
