有限集有序覆盖的若干计数问题

Some counting problems of ordered cover of finite set

讨论了有限集的可空有序覆盖和非空有序覆盖的计数问题,运用加法原理、乘法原理和容斥原理等计数技巧,得到一组满足各种条件的Nn的m组可空(非空)有序覆盖(A1,A2,Λ,Am)的计数公式.

Some counting problems about empty and unempty ordered cover of finite set were studied here. Through addition principle, multiplication principle and principle of inclusion and exclusion,a series of counting formulas about m groups (A_1,A_2,Λ,A_m) empty (unempty) ordered cover of N_n are obtained, which fit different kinds of conditions.