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 A231091 Number of distinct (modulo reflection and rotation) unicursal star polygons (not necessarily regular, no edge joins adjacent vertices) that can be formed by connecting the vertices of a regular n-gon. 2
 0, 0, 0, 0, 1, 1, 5, 27, 175, 1533, 14361, 151575, 1735869, 21594863 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,7 COMMENTS For polygons in general see A000939 and A000949, and especially the Golomb-Welch reference. - N. J. A. Sloane, Nov 21 2013 LINKS Stewart Gordon, The five possible stars for n=7 (SVG file) Wikipedia, Unicursal hexagram EXAMPLE For n=5, only solution is the regular pentagram. For n=6, only solution is the unicursal hexagram (see Wikipedia link). For n=7, two regular heptagrams and three irregular forms are possible. CROSSREFS Cf. A000939, A000940. Sequence in context: A091101 A185622 A225309 * A205774 A326094 A232683 Adjacent sequences:  A231088 A231089 A231090 * A231092 A231093 A231094 KEYWORD nonn,nice AUTHOR Stewart Gordon, Nov 03 2013 STATUS approved

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Last modified December 3 18:22 EST 2020. Contains 338910 sequences. (Running on oeis4.)