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EXAMPLE
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The sequence of terms together with their corresponding set-systems begins:
0: {}
1: {{1}}
20: {{1,2},{1,3}}
52: {{1,2},{1,3},{2,3}}
308: {{1,2},{1,3},{2,3},{1,4}}
820: {{1,2},{1,3},{2,3},{1,4},{2,4}}
2868: {{1,2},{1,3},{2,3},{1,4},{2,4},{3,4}}
68404: {{1,2},{1,3},{2,3},{1,4},{2,4},{3,4},{1,5}}
199476: {{1,2},{1,3},{2,3},{1,4},{2,4},{3,4},{1,5},{2,5}}
723764: {{1,2},{1,3},{2,3},{1,4},{2,4},{3,4},{1,5},{2,5},{3,5}}
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MATHEMATICA
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bpe[n_]:=Join@@Position[Reverse[IntegerDigits[n, 2]], 1];
stableQ[u_, Q_]:=!Apply[Or, Outer[#1=!=#2&&Q[#1, #2]&, u, u, 1], {0, 1}];
csm[s_]:=With[{c=Select[Subsets[Range[Length[s]], {2}], Length[Intersection@@s[[#]]]>0&]}, If[c=={}, s, csm[Sort[Append[Delete[s, List/@c[[1]]], Union@@s[[c[[1]]]]]]]]];
First/@GatherBy[Select[Range[0, 10000], stableQ[bpe/@bpe[#]]&&Length[csm[bpe/@bpe[#]]]<=1&], Length[bpe[#]]&]
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