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In mathematics, the sieve of Sundaram is a simple deterministic algorithm for finding all prime numbers up to a specified integer. It was discovered by Indian mathematician S. P. Sundaram in 1934. ==Algorithm== Start with a list of the integers from 1 to ''n''. From this list, remove all numbers of the form ''i'' + ''j'' + 2''ij'' where: * * The remaining numbers are doubled and incremented by one, giving a list of the odd prime numbers (i.e., all primes except 2) below 2''n'' + 2. The sieve of Sundaram sieves out the composite numbers just as sieve of Eratosthenes does, but even numbers are not considered; the work of "crossing out" the multiples of 2 is done by the final double-and-increment step. Whenever Eratosthenes' method would cross out ''k'' different multiples of a prime ''2i+1'', Sundaram's method crosses out ''i + j(2i+1)'' for . 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「Sieve of Sundaram」の詳細全文を読む スポンサード リンク
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