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 A268564 #11 Jun 09 2024 09:04:32 %S A268564 0,1,16,555,27155,1624602,110848296,8306916404,667683029392 %N A268564 Number of immersions of unoriented circle into oriented sphere with 2n double points such that two different choices of orientation of the circle are not related by geotopy. %H A268564 Robert Coquereaux and Jean-Bernard Zuber, <a href="https://doi.org/10.1142/S0218216516500474">Maps, immersions and permutations</a>, Journal of Knot Theory and Its Ramifications, Vol. 25, No. 8 (2016), 1650047; <a href="https://arxiv.org/abs/1507.03163">arXiv preprint</a>, arXiv:1507.03163 [math.CO], 2015-2016. See Eq. (16), s_s. %F A268564 a(n) = A008986(2*n) - A008987(2*n). - _Andrey Zabolotskiy_, Jun 05 2024 %Y A268564 Cf. A008986, A008987, A268563. %K A268564 nonn,more %O A268564 0,3 %A A268564 _N. J. A. Sloane_, Mar 02 2016 %E A268564 Name clarified and a(0), a(6)-a(8) added using formula by _Andrey Zabolotskiy_, Jun 08 2024