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 A289269 Number of polygonal tiles with n sides with two exits per side and n edges connecting pairs of exits, with no edges between exits on the same side and non-isomorphic under rotational and reflectional, i.e. dihedral, symmetry. 3
 0, 2, 4, 19, 80, 638, 6054, 76692, 1137284, 19405244, 370597430, 7825459362, 180862277352 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS The case n=2 is a degenerate polygon (two sides connecting two vertices). The two possibilities are when the edges cross and do not cross. Polygons start at n=3 with a triangle. LINKS Marko Riedel, Hexagonal tiles Marko Riedel, Maple code for number of tiles using Burnside lemma. CROSSREFS See A053871 for tiles with no symmetries being taken into account, A289191 for tiles with rotational symmetries only being taken into account. Sequence in context: A229485 A064228 A226891 * A272988 A168246 A212923 Adjacent sequences:  A289266 A289267 A289268 * A289270 A289271 A289272 KEYWORD nonn,more AUTHOR Marko Riedel, Jun 29 2017 STATUS approved

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Last modified August 17 17:04 EDT 2018. Contains 313816 sequences. (Running on oeis4.)