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A286139
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Number of connected induced (non-null) subgraphs of the n X n king graph.
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18
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1, 15, 388, 37196, 14765089, 24076152503, 159850328891568, 4290837646252661680, 463376724731585422732393, 200665409586497566263900755703, 347694350828123116321061347501951972, 2406781070555276417850396576804205226358828, 66481859567653621586313146932097075651519991887257
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OFFSET
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1,2
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LINKS
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MATHEMATICA
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Table[If[n<2, n, g = GraphData[{"King", {n, n}}]; -1 + ParallelSum[ Boole@ ConnectedGraphQ@ Subgraph[g, s], {s, Subsets@ Range[n^2]}]], {n, 4}]
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CROSSREFS
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Cf. A020873 (wheel), A059020 (ladder), A059525 (grid), A286182 (prism), A286183 (antiprism), A286184 (helm), A286185 (Möbius ladder), A286186 (friendship), A286187 (web), A286188 (gear), A286189 (rook), A285765 (queen).
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KEYWORD
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nonn,hard
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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