|
A cuban prime is a prime number that is a solution to one of two different specific equations involving third powers of ''x'' and ''y''. The first of these equations is: :〔Cunningham, On quasi-Mersennian numbers〕 and the first few cuban primes from this equation are : 7, 19, 37, 61, 127, 271, 331, 397, 547, 631, 919, 1657, 1801, 1951, 2269, 2437, 2791, 3169, 3571, 4219, 4447, 5167, 5419, 6211, 7057, 7351, 8269, 9241, 10267, 11719, 12097, 13267, 13669, 16651, 19441, 19927, 22447, 23497, 24571, 25117, 26227 The general cuban prime of this kind can be rewritten as , which simplifies to . This is exactly the general form of a centered hexagonal number; that is, all of these cuban primes are centered hexagonal. the largest known has 65537 digits with ,〔Caldwell, Prime Pages〕 found by Jens Kruse Andersen. The second of these equations is: :〔Cunningham, Binomial Factorisations, Vol. 1, pp. 245-259〕 This simplifies to . With a substitution it can also be written as . The first few cuban primes of this form are : :13, 109, 193, 433, 769, 1201, 1453, 2029, 3469, 3889, 4801, 10093, 12289, 13873, 18253, 20173, 21169, 22189, 28813, 37633, 43201, 47629, 60493, 63949, 65713, 69313 The name "cuban prime" has to do with the role cubes (third powers) play in the equations, and has nothing to do with Cuba. == See also == *Cubic function *List of prime numbers 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Cuban prime」の詳細全文を読む スポンサード リンク
|