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 A048781 Number of triangles in minimal triangle graphs. 1
 1, 2, 5, 13, 35, 86, 250, 687, 2001, 5897, 17847, 54683, 170578, 537468, 1714312, 5516392, 17910741, 58588966, 193035920, 640132185, 2135841554, 7167550473, 24186506740 (list; graph; refs; listen; history; text; internal format)
 OFFSET 3,2 COMMENTS a(n) is the total number of triples in all the minimal triangle graphs on n points. That is, a(n) = Sum |T| for all A000080(n) triangle graphs G(T) on n points. LINKS R. Bowen, The generation of minimal triangle graphs, Math. Comp. 21 (1967), 248-250. EXAMPLE For n=3 points there is one minimal triangle graph containing one triple, so a(3) = 1. For n=4 points there is one triangle graph containing two triples, so a(4) = 2. For n=5 points there are two graphs, containing two and three triples, respectively, so a(5) = 2+3 = 5. See also the illustration in A000080. CROSSREFS Cf. A000080. Sequence in context: A112839 A331755 A137674 * A291242 A097919 A160438 Adjacent sequences:  A048778 A048779 A048780 * A048782 A048783 A048784 KEYWORD nonn,more,nice AUTHOR Arlin Anderson (starship1(AT)gmail.com) EXTENSIONS Edited by N. J. A. Sloane, Jan 22 2014 a(17)-a(25) from Martin Fuller, Mar 23 2015 STATUS approved

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Last modified May 15 10:54 EDT 2021. Contains 343909 sequences. (Running on oeis4.)