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A054920
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Number of connected unlabeled reflexive relations with n nodes such that complement is also connected.
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1
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2, 4, 68, 2592, 278796, 95720106, 111891292036, 457846756500066, 6664787020904248568, 349363873490889302878250, 66602024342830108271942323060, 46557190064705399729526041154647820
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OFFSET
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1,1
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LINKS
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FORMULA
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MATHEMATICA
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A000595 = Import["https://oeis.org/A000595/b000595.txt", "Table"][[All, 2]];
(* EulerInvTransform is defined in A022562 *)
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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