{5,-8,11,-14,17,-20,23}的真子集列举
1、集合A为7个元素,列举该集合的全部子集。

3、有2个元素的子集情况,此时个数为C(7,2)=21个,A10={5,-8},A11={5,11},A12={5,-14};帆歌达缒A13={5,17},A14={5,-20},A15={5,23};A16={-8,11},A17={-8,-14},A18={-8,17};A19={-8,-20},A20={-8,23},A21={11,-14};A22={11,17},A23={11,-20},A24={11,23};A25={-14,17},A26={-14,-20},A27={-14,23};A28={17,-20},A29={17,23},A30={-20,23};



9、A111={5,11,-14,17,-20}, A112={5,11,-14,17,23};A113={5,11,-14,-20,23}, A114={5,11,17,-20,23};A115={5,-14,17,-20,23}, A116={-8,11,-14,17,-20};A117={-8,11,-14,17,23}, A118={-8,11,-14,-20,23};A119={-8,11,17,-20,23}, A120={-8,-14,17,-20,23};A121={11,-14,17,-20,23};
