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19th Century In Sierra Leone
19 (nineteen) is the natural number following 18 and preceding 20. It is a prime number. Mathematics 19 is the eighth prime number, and forms a sexy prime with 13, a twin prime A twin prime is a prime number that is either 2 less or 2 more than another prime number—for example, either member of the twin prime pair (41, 43). In other words, a twin prime is a prime that has a prime gap of two. Sometimes the term ''twin pr ... with 17 (number), 17, and a cousin prime with 23 (number), 23. It is the third full reptend prime, the fifth Trinomial triangle#Central trinomial coefficients, central trinomial coefficient, and the seventh Mersenne prime exponent. It is also the second Keith number, and more specifically the first Keith prime. * 19 is the maximum number of fourth powers needed to sum up to any natural number, and in the context of Waring's problem, 19 is the fourth value of Waring's problem#The number g(k), g(k). * The sum of the squares of the first 19 primes is d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nonadecimal
There are many different numeral systems, that is, writing systems for expressing numbers. By culture / time period By type of notation Numeral systems are classified here as to whether they use positional notation (also known as place-value notation), and further categorized by radix or base. Standard positional numeral systems The common names are derived Hexadecimal#Etymology, somewhat arbitrarily from a mix of Latin and Greek language, Greek, in some cases including roots from both languages within a single name. There have been some proposals for standardisation. Non-standard positional numeral systems Bijective numeration Signed-digit representation Negative bases The common names of the negative base numeral systems are formed using the prefix ''nega-'', giving names such as: Complex-base system, Complex bases Non-integer representation, Non-integer bases p-adic number, ''n''-adic number Mixed radix * Factorial number system * Even double factorial ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
