This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A156809 #13 Jul 22 2025 06:21:30 %S A156809 1,2,4,11,34,154,978,9497,127954,2165291,42609994,937233306, %T A156809 22576188846 %N A156809 Number of nonisomorphic circle graphs of order n. %H A156809 R. Arratia, B. Bollobas, D. Coppersmith, and G. B. Sorkin, <a href="https://doi.org/10.1016/S0166-218X(00)00190-6">Euler circuits and DNA sequencing by hybridization</a>, Discrete Appl. Math., 104 (2000), 63-96. %H A156809 Gi-Sang Cheon, Jinha Kim, Minki Kim, Sergey Kitaev, <a href="https://arxiv.org/abs/1803.01055">On k-11-representable graphs</a>, arXiv:1803.01055 [math.CO], 2018. %H A156809 L. E. Danielsen and M. G. Parker, <a href="https://arxiv.org/abs/0804.2576">Interlace polynomials: Enumeration, unimodality, and connections to codes</a>, arXiv:0804.2576 [math.CO], 2008-2009. %H A156809 L. E. Danielsen, <a href="http://www.ii.uib.no/~larsed/circle/">Database of Circle Graphs</a>. %Y A156809 Cf. A156808. %K A156809 hard,nonn %O A156809 1,2 %A A156809 Lars Eirik Danielsen (larsed(AT)ii.uib.no), Feb 16 2009 %E A156809 a(13) from _Tom Johnston_, Oct 17 2020