一個複雜的排列組合問題 - 拼圖

By Carol
at 2008-02-07T13:36
at 2008-02-07T13:36
Table of Contents
昨晚守歲看電影太累了Orz 所以弄錯了
應該是這樣:
由排容原理得10個客人恰選了n種的選法有
n-1 i 10
C(8,n)* Σ (-1) * C(n,i)*(n-i)
i=0
例如恰選了1種的選法是 C(8,1)*1^10
恰選了2種的選法是 C(8,2)*(2^10-2*1^10)
恰選了3種的選法是 C(8,3)*(3^10-3*2^10+3*1^10)
etc.
因此所求答案就是
1 8 n-1 i 10
------ Σ n*C(8,n)*Σ (-1) * C(n,i)*(n-i)
8^10 n=1 i=0
這樣Mathematica求出來的也是5.89多了
--
但是我目前還想不到怎麼化簡 Orz
--
'You've sort of made up for it tonight,' said Harry. 'Getting the
sword. Finishing the Horcrux. Saving my life.'
'That makes me sound a lot cooler then I was,' Ron mumbled.
'Stuff like that always sounds cooler then it really was,' said
Harry. 'I've been trying to tell you that for years.'
-- Harry Potter and the Deathly Hollows, P.308
--
Tags:
拼圖
All Comments

By Rachel
at 2008-02-11T01:14
at 2008-02-11T01:14

By Leila
at 2008-02-11T23:51
at 2008-02-11T23:51

By Victoria
at 2008-02-13T05:00
at 2008-02-13T05:00
Related Posts
一個複雜的排列組合問題

By Emily
at 2008-02-07T01:59
at 2008-02-07T01:59
一個複雜的排列組合問題

By Andrew
at 2008-02-06T10:28
at 2008-02-06T10:28
請問台中地區哪裡有賣空白拼圖呢?

By Oscar
at 2008-02-04T14:43
at 2008-02-04T14:43
雷諾瓦台大店

By Linda
at 2008-02-03T22:54
at 2008-02-03T22:54
恆河沙

By Olive
at 2008-02-01T18:22
at 2008-02-01T18:22