奢侈數

出自維基百科,自由嘅百科全書
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奢侈數英文Extravagant number),又叫浪費數英文Wasteful number),係指一正整數質因數分解英文Integer factorization(包括指數)嘅總位數大過整數本身嘅位數[1]。例如喺十進位中,4 = 22,6 = 2×3,8 = 23,9 = 32,質因數分解嘅總位數都比整數位數多,因此都係奢侈數。

前幾個奢侈數為:4, 6, 8, 9, 12, 18, 20, 22, 24, 26, 28, 30, 33, 34, 36, 38, 39, 40, 42, 44, 45, 46, 48, 50, 51, 52, 54, 55, 56, 57, 58, 60, 62, 63, 65, 66, 68, 69, 70, 72, 74, 75, 76, 77, 78, 80, 82, 84, 85, 86, 87, 88, 90, 91, 92, 93, 94, 95, 96, 98, 99, 100(OEIS中嘅數列A046760

任何進制下都可以定義奢侈數,而且無論喺邊一種進制,都存在無限咁多個奢侈數[1]

睇埋[編輯]

參考資料[編輯]

  1. 1.0 1.1 Darling, David J. (2004). [http ://books.google.com/books?id=nnpChqstvg0C&pg=PA102 The universal book of mathematics: from Abracadabra to Zeno's paradoxes] Check |url= value (help). John Wiley & Sons. p. 102. ISBN 978-0-471-27047-8.