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 A307450 Number of cubic graphs with minimal crossing number n and the minimal possible number of vertices. 1
 1, 1, 2, 8, 2, 2, 3, 4, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 COMMENTS a(0) = 1 from the complete graph K_4. a(1) = 1 from the utility graph K_{3,3}. a(2) = 2 from the Petersen graph (and 1 other). a(3) = 8 from the Heawood graph, GP(7,2) (and 6 others). a(4) = 2 from the Moebius-Kantor and 8-crossed prism graphs. a(5) = 2 from the Pappus graph (and 1 other). a(6) = 3 from the Desargues graph (and 2 others based on 10_3 configurations). a(7) = 4 from the 7-crossing graphs (4 in total). a(8) = 3 from the McGee and Nauru graphs (and 1 other). a(9) >= 3 from GP(13,5), the Coxeter-1, and McGee+1 graphs (and unknown others). - Eric W. Weisstein, Apr 12 2019 a(10) >= 2 from the Levi-1 (=McGee+2) graph and graph from 2019 Clancy et al. preprint (and unknown others). - Eric W. Weisstein, Apr 12 2019 a(11) >= 1 from the Coxeter graph (and unknown others). a(13) >= 1 from the Levi graph (and unknown others). LINKS A. E. Brouwer, The Heawood Graph Geoff Exoo, Rectilinear Drawings of Famous Graphs Michael Haythorpe and Alex Newcombe, There are no Cubic Graphs on 26 Vertices with Crossing Number 11, arXiv preprint arXiv:1804.10336 [math.CO], 2018. Ed Pegg, Jr., Cubic Symmetric Graphs Ed Pegg, Jr., Cubic Symmetric Graphs Eric Weisstein's World of Mathematics, Smallest Cubic Crossing Number Graph CROSSREFS Cf. A110507. Sequence in context: A194567 A065813 A076344 * A173686 A090975 A257579 Adjacent sequences:  A307447 A307448 A307449 * A307451 A307452 A307453 KEYWORD nonn,more AUTHOR Ed Pegg Jr, Apr 08 2019 STATUS approved

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Last modified January 23 22:36 EST 2020. Contains 331177 sequences. (Running on oeis4.)