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 A006647 Number of graphs with n nodes, n-2 edges and no isolated vertices. (Formerly M2586) 1
 1, 1, 3, 6, 15, 33, 83, 202, 527, 1377, 3744, 10335, 29297, 84396, 248034, 740289, 2245094, 6904206, 21522973, 67936799, 217026480, 701159919, 2289925258, 7556363054, 25184139149, 84743377436, 287815771822, 986345040471, 3409869008578 (list; graph; refs; listen; history; text; internal format)
 OFFSET 4,3 REFERENCES N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). LINKS W. L. Kocay, Some new methods in reconstruction theory, pp. 89 - 114 of Combinatorial Mathematics IX. Proc. Ninth Australian Conference (Brisbane, August 1981). Ed. E. J. Billington, S. Oates-Williams and A. P. Street. Lecture Notes Math., 952. Springer-Verlag, 1982. FORMULA a(n) = A001430(n) - A001433(n - 1). - Sean A. Irvine, Jun 05 2017 CROSSREFS Cf. A001430, A001433. Sequence in context: A105476 A000599 A063832 * A032126 A190525 A032176 Adjacent sequences:  A006644 A006645 A006646 * A006648 A006649 A006650 KEYWORD nonn AUTHOR EXTENSIONS More terms from Vladeta Jovovic, Mar 02 2008 More terms from Sean A. Irvine, Jun 05 2017 STATUS approved

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Last modified December 7 22:29 EST 2019. Contains 329850 sequences. (Running on oeis4.)