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]]]]];
edgeConnSys[sys_]:=如果[Length[csm[sys]]=1,0,长度[sys]-最大@@Length/@Select[Union[Subsets[sys]],长度[csm[#]]=1&]];
表[Length[Select[Subsets[Subsets[Range[n],{2}]],edgeConnSys[#]=k&]],{n,0,4},{k,0,二项式[n,2]}]//。{敌人___,0}:>{敌人}