回复：Yes, I think C(6,3)*2*2+6!/6=200..

来源: 于 2012-05-04 07:59:37 [旧帖] [给我悄悄话] 本文已被阅读：次

I am a slow guy, let's slow down a bit,

 

Two parts: 123   456

           132   456

           123   465

           132   465

How about we first select 456 which is counted as new one in C(6,3)? We would have

           456 123

           456 132

           465 123

           465 132

doubly counted in your original calculation.

Does my thinking make sense?