emmevi Cushion Cover Sofa 42 x 42 cm Solid Color Zippered Cushion Cover

Product Information

What makes a number particularly interesting or uninteresting is a question that mathematician and psychologist Nicolas Gauvrit, computational natural scientist Hector Zenil and I have studied, starting with an analysis of the sequences in the OEIS. Aside from a theoretical connection to Kolmogorov complexity (which defines the complexity of a number by the length of its minimal description), we have shown that the numbers contained in Sloane’s encyclopedia point to a shared mathematical culture and, consequently, that OEIS is based as much on human preferences as pure mathematical objectivity. Problem of the Sum of Three Cubes Everyone loves unsolved mysteries. Examples include Amelia Earhart’s disappearance over the Pacific in 1937 and the daring escape of inmates Frank Morris and John and Clarence Anglin from Alcatraz Island in California in 1962. Moreover our interest holds even if the mystery is based on a joke. Take author Douglas Adams’s popular 1979 science-fiction novel The Hitchhiker’s Guide to the Galaxy, the first in a series of five. Toward the end of the book, the supercomputer Deep Thought reveals that the answer to the “Great Question” of “Life, the Universe and Everything” is “forty-two.” The number is the sum of the first three odd powers of two—that is, 2 1 + 2 3 + 2 5 = 42. It is an element in the sequence a( n), which is the sum of n odd powers of 2 for n> 0. The sequence corresponds to entry A020988 in The On-Line Encyclopedia of Integer Sequences (OEIS), created by mathematician Neil Sloane. In base 2, the nth element may be specified by repeating 10 n times (1010 ... 10). The formula for this sequence is a( n) = (2/3)(4 n– 1). As n increases, the density of numbers tends toward zero, which means that the numbers belonging to this list, including 42, are exceptionally rare. We can also convert by utilizing the inverse value of the conversion factor. In this case 1 inch is equal to 0.06047619047619 × 42 centimeters.

You cannot get a sum of 4 or 5 (= –4). This restriction means that sums of three cubes are never numbers of the form 9 m + 4 or 9 m + 5. We thus say that n = 9 m + 4 and n = 9 m + 5 are prohibited values. Searching for Solutions The cases of 165, 795 and 906 were also solved recently. For integers below 1,000, only 114, 390, 579, 627, 633, 732, 921 and 975 remain to be solved. Computer scientists and mathematicians recognize the appeal of the number 42 but have always thought that it was a simple game that could be played just as well with another number. Still, a recent news item caught their attention. When it was applied to the “sum of three cubes” problem, 42 was more troublesome than all the other numbers below 100. In ancient Egyptian mythology, during the judgment of souls, the dead had to declare before 42 judges that they had not committed any of 42 sins.Booker and Sutherland discussed the algorithmic strategy to be used in the search for a solution to 42. As Booker found with his solution to 33, they knew they didn’t have to resort to trying all of the possibilities for x, y, and z. All this is amusing, but it would be wrong to say that 42 is really anything special mathematically. The numbers 41 and 43, for example, are also elements of many sequences. You can explore the properties of various numbers on Wikipedia. The author’s choice of the number 42 has become a fixture of geek culture. It’s at the origin of a multitude of jokes and winks exchanged between initiates. If, for example, you ask your search engine variations of the question “What is the answer to everything?” it will most likely answer “42.” Try it in French or German. You’ll often get the same answer whether you use Google, Qwant, Wolfram Alpha (which specializes in calculating mathematical problems) or the chat bot Web app Cleverbot.

Note that for some integer values of n, the equation n = a 3 + b 3 + c 3 has no solution. Such is the case for all integers n that are expressible as 9 m + 4 or 9 m + 5 for any integer m (e.g., 4, 5, 13, 14, 22, 23). Demonstrating this assertion is straightforward: we use the “modulo 9” (mod 9) calculation, which is equivalent to assuming that 9 = 0 and then manipulating only numbers between 0 and 8 or between −4 and 4. When we do so, we see that: For the sum of cubes, some solutions may be surprisingly large, such as the one for 156, which was discovered in 2007: mod 9); 1 3 = 1 (mod 9); 2 3 = 8 = –1 (mod 9); 3 3 = 27 = 0 (mod 9); 4 3 = 64 = 1 (mod 9); 5 3 = (–4) 3 = –64 = –1 (mod 9); 6 3 = (–3) 3 = 0 (mod 9); 7 3 = (–2) 3 = 1 (mod 9); 8 3 = (–1) 3 = –1 (mod 9) In 2009, employing a method proposed by Noam Elkies of Harvard University in 2000, German mathematicians Andreas-Stephan Elsenhans and Jörg Jahnel explored all the triplets a, b, c of integers with an absolute value less than 10 14 to find solutions for n between 1 and 1,000. The paper reporting their findings concluded that the question of the existence of a solution for numbers below 1,000 remained open only for 33, 42, 74, 114, 165, 390, 579, 627, 633, 732, 795, 906, 921 and 975. For integers less than 100, just three enigmas remained: 33, 42 and 74.An infinite set of solutions is also known for n = 2. It was discovered in 1908 by mathematician A. S. Werebrusov. For any integer p: The method of using Charity Engine is similar to part of the plot surrounding the number 42 in the "Hitchhiker" novel: After Deep Thought’s answer of 42 proves unsatisfying to the scientists, who don’t know the question it is meant to answer, the supercomputer decides to compute the Ultimate Question by building a supercomputer powered by Earth … in other words, employing a worldwide massively parallel computation platform.

By multiplying each term of these equations by the cube of an integer ( r3), we deduce that there are also infinitely many solutions for both the cube and double the cube of any integer.Booker and Sutherland say there are 10 more numbers, from 101-1000, left to be solved, with the next number being 114. The number 42 is the sum of the first two nonzero integer powers of six—that is, 6 1 + 6 2 = 42. The sequence b( n), which is the sum of the powers of six, corresponds to entry A105281 in OEIS. It is defined by the formulas b(0) = 0, b( n) = 6 b( n– 1) + 6. The density of these numbers also tends toward zero at infinity. The number 42 is especially significant to fans of science fiction novelist Douglas Adams’ “The Hitchhiker’s Guide to the Galaxy, ” because that number is the answer given by a supercomputer to “the Ultimate Question of Life, the Universe, and Everything.” Deep Thought takes 7.5 million years to calculate the answer to the ultimate question. The characters tasked with getting that answer are disappointed because it is not very useful. Yet, as the computer points out, the question itself was vaguely formulated. To find the correct statement of the query whose answer is 42, the computer will have to build a new version of itself. That, too, will take time. The new version of the computer is Earth. To find out what happens next, you’ll have to read Adams’s books. The marathon distance of 42.195 kilometers corresponds to the legend of how far the ancient Greek messenger Pheidippides traveled between Marathon and Athens to announce victory over the Persians in 490 B.C. (The fact that the kilometer had not yet been defined at that time only makes the connection all the more astonishing.)