Integers Free of Large Prime Factors
نویسنده
چکیده
Deene (x;y) to be the number of positive integers n x such that n has no prime divisor larger than y. We present a simple algorithm that approximates (x; y) in O(yf log log x log y + 1 log log y g) oating point operations. This algorithm is based directly on a theorem of Hildebrand and Tenenbaum. We also present data which indicate that this algorithm is more accurate in practice than other known approximations, including the well-known approximation (x;y) xx(log x= log y), where (u) is Dickman's function.
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تاریخ انتشار 1997