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 A210507 Number of labeled graphs on [n] with unicyclic components containing a given edge. 0
 1, 10, 111, 1468, 22940, 416250, 8626660, 201349672, 5230931454, 149783426470, 4688281021490, 159284662406460, 5838769123729984, 229711022253150382, 9655348958575618320, 431845990498159342000, 20479127764425617465660, 1026429489947790074019978 (list; graph; refs; listen; history; text; internal format)
 OFFSET 3,2 COMMENTS This gives the number of matroid bases that contain a given element (edge) of the bicircular matroid of K_n. REFERENCES O. GimÃ©nez, A. de Mier, M. Noy, On the Number of Bases of Bicircular Matroids, Ann. Comb. 9 (2005), no. 1, 35-45. LINKS FORMULA a(n) = 2*b(n)/(n-1), where b(n) is seq A137916. EXAMPLE a(4)=10 means that 10 (of the 15) labeled unicyclic graphs on 4 vertices contain a given edge. CROSSREFS Cf. A137916. Sequence in context: A122574 A176736 A084031 * A066275 A046164 A322724 Adjacent sequences:  A210504 A210505 A210506 * A210508 A210509 A210510 KEYWORD nonn AUTHOR Gary Gordon, Jan 25 2013 STATUS approved

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Last modified August 23 14:00 EDT 2019. Contains 326229 sequences. (Running on oeis4.)