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In additive number theory, the Schnirelmann density of a sequence of numbers is a way to measure how "dense" the sequence is. It is named after Russian mathematician L.G. Schnirelmann, who was the first to study it.〔Schnirelmann, L.G. (1930). "(On the additive properties of numbers )", first published in "Proceedings of the Don Polytechnic Institute in Novocherkassk" (in Russian), vol XIV (1930), pp. 3-27, and reprinted in "Uspekhi Matematicheskikh Nauk" (in Russian), 1939, no. 6, 9–25.〕〔Schnirelmann, L.G. (1933). First published as "(Über additive Eigenschaften von Zahlen )" in "Mathematische Annalen" (in German), vol 107 (1933), 649-690, and reprinted as "(On the additive properties of numbers )" in "Uspekhin. Matematicheskikh Nauk" (in Russian), 1940, no. 7, 7–46.〕 ==Definition== The Schnirelmann density of a set of natural numbers ''A'' is defined as : where ''A''(''n'') denotes the number of elements of ''A'' not exceeding ''n'' and inf is infimum.〔Nathanson (1996) pp.191–192〕 The Schnirelmann density is well-defined even if the limit of ''A''(''n'')/''n'' as fails to exist (see asymptotic density). 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「Schnirelmann density」の詳細全文を読む スポンサード リンク
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