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A054940
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Number of connected labeled graphs with n nodes and an odd number of edges.
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0
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0, 1, 1, 22, 352, 13412, 932768, 125776816, 33148125376, 17248244478848, 17820828772662272, 36677298103403269504, 150636101324831804975104, 1235824405515221870758956032, 20263840468865240117261288526848, 664289479167891600504170147259897856
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OFFSET
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1,4
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LINKS
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FORMULA
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MATHEMATICA
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nn = 15; Clear[f]; f[z_] := Sum[(1 + u)^Binomial[n, 2] z^n/n!, {n, 0, nn + 1}]; Drop[Map[Total[#[[2 ;; Binomial[nn, 2] ;; 2]]] &, Range[0, nn]! CoefficientList[Series[ Log[f[z]] , {z, 0, nn}], {z, u}]], 1] (* Geoffrey Critzer, Jul 27 2016 *)
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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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