推 huming103:可以跟第一題一樣大小的anti-symmetric有幾種 03/12 11:43
推 james1815:（b）:2^(n*(n-1)/2) 對角線必選,而對角線以外選一個 03/12 14:28
→ Lautreamont:恩 我了解了 謝謝 03/12 14:37
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"?
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