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A133206
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Number of unlabeled graphs with n nodes and a degenerate adjacency matrix.
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1
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1, 1, 3, 7, 25, 99, 690, 6551, 133174, 4138641, 290045659
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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1,3
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COMMENTS
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LINKS
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MATHEMATICA
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k = {}; For[i = 1, i < 8, i++, lg = ListGraphs[i] ; len = Length[lg]; k = Append[k, Length[Select[Range[len], Det[ToAdjacencyMatrix[lg[[ # ]]]] == 0 &]]]]; k
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CROSSREFS
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KEYWORD
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more,nonn
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AUTHOR
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STATUS
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approved
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