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看板Grad-ProbAsk作者 (Maldoror is dead)時間14年前 (2010/03/12 11:14), 編輯推噓2(201)
留言3則, 3人參與, 最新討論串1/4 (看更多)
Let A be a set with |A|=n, and let R be a relation on A that is anti-symmetric. (a) What is the maximum value for |R|? (b) How many anti-symmetric relations can have the size? Ans: ^^^^^^^^^^^^^^^^^^ (a) n*(n+1)/2 (b) 請問什麼叫做"can have the size"? -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 118.160.180.232

03/12 11:43, , 1F
可以跟第一題一樣大小的anti-symmetric有幾種
03/12 11:43, 1F

03/12 14:28, , 2F
(b):2^(n*(n-1)/2) 對角線必選,而對角線以外選一個
03/12 14:28, 2F

03/12 14:37, , 3F
恩 我了解了 謝謝
03/12 14:37, 3F
文章代碼(AID): #1BcR6DuO (Grad-ProbAsk)
文章代碼(AID): #1BcR6DuO (Grad-ProbAsk)