csm[s_]:=使用[{c=Select[Tuples[Range[Length[s]],2],And[OrderedQ[#],UnsameQ@@#,Length[Intersection@@s[[#]]>0]&]},如果[c=={},s,csm[Sort[Append[Delete[s,List/@c[[1]]],Union@@s[[c[1]]]]];
表[Length[Select[Subsets[Subsets[Range[n],{2}]],Length[csm[#]]<=1&]],{n,0,5}]