7个元素集合的子集与真子集解析穷举法举例(134)
1、元素最少时,即1个元素也没有,此时有子集A1=∅;
元素最多时,即有7个元素,此时有子集A2=A,即:
A2={37,38,39,40,41,42,43}。

1、此时个数为C(7,1)=7个,列举如下:
A3={37},A4={38},A5={39};
A6={40},A7={41},A8={42};
A9={43};

1、此时个数为C(7,2)=21个,列举如下:
A10={37,38},A11={37,39},A12={37,40};
A13={37,41},A14={37,42},A15={37,43};
A16={38,39},A17={38,40},A18={38,41};
A19={38,42},A20={38,43},A21={39,40};
A22={39,41},A23={39,42},A24={39,43};
A25={40,41},A26={40,42},A27={40,43};
A28={41,42},A29={41,43},A30={42,43};

1、此时个数为C(7,3)=35个,列举如下:
A31={37,38,39},A32={37,38,40},A33={37,38,41};
A34={37,38,42},A35={37,38,43},A36={37,39,40};
A37={37,39,41},A38={37,39,42},A39={37,39,43};
A40={37,40,41},A41={37,40,42},A42={37,40,43};
A43={37,41,42},A44={37,41,43},A45={37,42,43};
A46={38,39,40},A47={38,39,41},A48={38,39,42};

2、A49={38,39,43},A50={38,40,41},A51={38,40,42};
A52={38,40,43},A53={38,41,42},A54={38,41,43};
A55={38,42,43},A56={39,40,41},A57={39,40,42};
A58={39,40,43},A59={39,41,42},A60={39,41,43};
A61={39,42,43},A62={40,41,42},A63={40,41,43};
A64={40,42,43}, A65={41,42,43};

1、此时个数为C(7,4)=C(7,3)=35个,列举如下:
A66={37,38,39,40},A67={37,38,39,41};
A68={37,38,39,42}, A69={37,38,39,43};
A70={37,38,40,41},A71={37,38,40,42};
A72={37,38,40,43},A73={37,38,41,42};
A74={37,38,41,43}, A75={37,38,42,43};
A76={37,39,40,41}, A77={37,39,40,42};
A78={37,39,40,43}, A79={37,39,41,42};
A80={37,39,41,43}, A81={37,39,42,43};

2、A82={37,40,41,42}, A83={37,40,41,43};
A84={37,40,42,43}, A85={37,41,42,43};
A86={38,39,40,41}, A87={38,39,40,42};
A88={38,39,40,43}, A89={38,39,41,42};
A90={38,39,41,43}, A91={38,39,42,43};
A92={38,40,41,42}, A93={38,40,41,43};
A94={38,40,42,43}, A95={38,41,42,43};
A96={39,40,41,42}, A97={39,40,41,43};
A98={39,40,42,43}, A99={39,41,42,43};
A100={40,41,42,43};

1、此时个数为C(7,5)=C(7,2)=21个,列举如下:
A101={37,38,39,40,41}, A102={37,38,39,40,42};
A103={37,38,39,40,43}, A104={37,38,39,41,42};
A105={37,38,39,41,43}, A106={37,38,39,42,43};
A107={37,38,40,41,42}, A108={37,38,40,41,43};
A109={37,38,40,41,43}, A110={37,38,41,42,43};

2、
A111={37,39,40,41,42}, A112={37,39,40,41,43};
A113={37,39,40,42,43}, A114={37,39,41,42,43};
A115={37,40,41,42,43}, A116={38,39,40,41,42};
A117={38,39,40,41,43}, A118={38,39,40,42,43};
A119={38,39,41,42,43}, A120={38,40,41,42,43};
A121={39,40,41,42,43};

1、此时个数为C(7,6)=C(7,1)=7个,列举如下:
A122={37,38,39,40,41,42};
A123={37,38,39,40,41,43};
A124={37,38,39,40,42,43};
A125={37,38,39,41,42,43};
A126={37,38,40,41,42,43};
A127={37,39,40,41,42,43};
A128={38,39,40,41,42,43}。
