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 A054907 #19 Jan 25 2025 11:27:46 %S A054907 1,0,0,0,0,0,0,0,1,0,0,0,1,0,1,1,3,1,4,3,12,12,28,49,180,368,1901, %T A054907 14493,357003 %N A054907 Number of n-dimensional unimodular lattices (or quadratic forms) containing no vectors of norm 1. %D A054907 J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 49. %H A054907 Gaëtan Chenevier, <a href="https://arxiv.org/abs/2104.06846">Statistics for Kneser p-neighbors</a>, arXiv:2104.06846 [math.NT], 2021. %H A054907 Gaëtan Chenevier, <a href="http://gaetan.chenevier.perso.math.cnrs.fr/pub.html">Publications</a>, in particular <a href="http://gaetan.chenevier.perso.math.cnrs.fr/unimodular_lattices/unimodular_lattices.gp">The rank n unimodular lattices with no norm 1 vector, for 1<=n<=27</a> and <a href="http://gaetan.chenevier.perso.math.cnrs.fr/unimodular_lattices/notice_dim28.txt">The rank 28 unimodular lattices with no norm 1 vector</a>. %H A054907 Gaëtan Chenevier, <a href="http://gaetan.chenevier.perso.math.cnrs.fr/Unimodular_hunting_oberwolfach.pdf ">Unimodular hunting</a>, Modular Forms Workshop, Oberwolfach online, Feb 2021. %F A054907 If 8|n then a(n) = A054908(n) + A054909(n/8), otherwise a(n) = A054908(n). - _Andrey Zabolotskiy_, Nov 05 2021 %Y A054907 Cf. A005134 (cumulative sums), A054908, A054909, A054911. %K A054907 nonn,nice,hard %O A054907 0,17 %A A054907 _N. J. A. Sloane_, May 23 2000 %E A054907 a(26)-a(28) added from Gaëtan Chenevier's page by _Andrey Zabolotskiy_, Nov 05 2021