包含排斥定律:否定形式 没有被包含在若干个子集的并集中的元素个数: N(AAA)=N-S+S2-S3+.+(-1)Sk+.+(-1)"Sn where,S=∑lA,nA,∩nA.lk=l,2,n l≤i1≤i2≤.ik≤n For an example:the formula for 4 subsets N-(IS+S2+IS3+S4D) +(IS1⌒S2+lS1∩S2+S1∩S4+lS2S3+lS2⌒S4+lS3S40 -(IS1nS2S3+lS1nS2∽S4+lS1∩S3∽S4+lS2⌒S3⌒S4) +lS1∩S2nS3nS4l包含-排斥定律: 否定形式 = = = − + − + + − + + − i i i n k i i i n n k k n k k S A A A k n N A A A N S S S S S 1 ... 1 2 1 2 3 1 2 1 2 where | ... | 1,2,..., ( ... ) ... ( 1) ... ( 1) , For an example:the formula for 4 subsets N - (|S1 |+ |S2 |+ |S3 |+ |S4 |) + (|S1S2 |+|S1S2 |+|S1S4 |+|S2S3 |+|S2S4 |+|S3S4 |) - (|S1S2S3 |+|S1S2S4 |+|S1S3S4 |+|S2S3S4 |) + |S1S2S3S4 | 没有被包含在若干个子集的并集中的元素个数: