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 A165452 Number of connected graphs of odd girth at least 7 with n vertices. 1
 1, 1, 1, 3, 5, 17, 45, 184, 748, 4143, 26532, 221032, 2326853, 32202266, 589436301, 14459238676, 477812658943 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS The odd girth of a graph is the length of a shortest cycle of odd length. Thus, these are the connected graphs that do not have a triangle or C_5 as induced subgraph. - Falk Hüffner, Jan 15 2016 The bipartite graphs (which have no odd cycles) are included. LINKS F. Hüffner, tinygraph, software for generating integer sequences based on graph properties, version ece94ef. CROSSREFS Cf. A005142, A024607. Inverse EULER transform of A345247. Sequence in context: A236458 A131342 A005142 * A106063 A215106 A006483 Adjacent sequences:  A165449 A165450 A165451 * A165453 A165454 A165455 KEYWORD nonn AUTHOR Friedrich Regen (friedrich.regen(AT)tu-ilmenau.de), Sep 20 2009 EXTENSIONS a(15) and a(16) added using tinygraph by Falk Hüffner, Jan 15 2016 a(17) added by Brendan McKay, Jun 12 2021 STATUS approved

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Last modified September 21 07:28 EDT 2021. Contains 347596 sequences. (Running on oeis4.)