In this paper, we discuss the counting prob lem of an order n-group of set (A 1,A 2,…,A n) which satisfies ∪ni=1A i={a 1,a 2,…,a m} and one of the following: (1) ∩ni=1A i=Φ; (2) ∩ni=1A i={b 1,b 2,…,b k};(3)...In this paper, we discuss the counting prob lem of an order n-group of set (A 1,A 2,…,A n) which satisfies ∪ni=1A i={a 1,a 2,…,a m} and one of the following: (1) ∩ni=1A i=Φ; (2) ∩ni=1A i={b 1,b 2,…,b k};(3) ∩ni=1A 1{b 1,b 2,…,b k}; (4) A i≠Φ (i=1,2,…,k). We solve these problems by element analytical meth od.展开更多
文摘In this paper, we discuss the counting prob lem of an order n-group of set (A 1,A 2,…,A n) which satisfies ∪ni=1A i={a 1,a 2,…,a m} and one of the following: (1) ∩ni=1A i=Φ; (2) ∩ni=1A i={b 1,b 2,…,b k};(3) ∩ni=1A 1{b 1,b 2,…,b k}; (4) A i≠Φ (i=1,2,…,k). We solve these problems by element analytical meth od.