容斥原理的推广

The Promotion of Permutations Principle

把容斥原理形式进一步的推广得到一些更普遍的形式.对于任何一个集合S,推广到在性质a1,a2,…,aq中具有r个性质,在性质aq+1,…,an中具有k个性质的元素的个数为:N(r,k)=∑0≤i≤q-r 0≤j≤n-q-k(-1)i+j(r+i r)(k+j k)N r+i,k+j,使得容斥原理的应用范围扩大化.

By further promoting the principle of permutations form some of the more common form are ob-tained.To any aggregation S,……the number of element with r character inα1,α2…,αq,and k character in αq＋1,…,αn,is determined by N（r,k）=∑0≤i≤q-r 0≤j≤n-q-k（-1）i＋j（r＋i r）（k＋j k）N r＋i,k＋j,.The applications of permutations principle are enlarged.