摘要:a1.a2.a3.a4.-a99的“凯森和 = 991 .
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设集合P={1,2,3,4,5,6,7,8,9,10},P的子集A={a1,a2,a3},其中a1<a2<a3,当满足a3≥a2+3≥a1+6时,称子集A为P的“好子集”,则P的“好子集”的个数为
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