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 A309018 #12 Feb 22 2021 10:33:58
%S A309018 24200,7379216,41934482,4357599552,55820091938,3827188349968,
%T A309018 69206906601800,3876306765700644,83804387156528018,
%U A309018 4161957566985310208,100644292294423977842,4601436044608986037284,120511830300023778605000,5179981855242249681088528,144148769049390803580105218
%N A309018 Number of perfect matchings in the graph C_{12} X C_n.
%C A309018 This sequence satisfies a recurrence relation of order 266.
%H A309018 Seiichi Manyama, <a href="/A309018/b309018.txt">Table of n, a(n) for n = 3..500</a>
%H A309018 S. N. Perepechko, <a href="http://www.jip.ru/2016/333-361-2016.pdf">The number of perfect matchings on C_m X C_n graphs</a>, (in Russian), Information Processes, 2016, V. 16, No. 4, pp. 333-361.
%H A309018 Sergey Perepechko, <a href="/A309018/a309018.pdf">Generating function</a> in Maple notation.
%Y A309018 Row n=6 of A341741.
%Y A309018 Cf. A230033, A231485, A232804, A253678, A281583, A281679, A308761.
%K A309018 nonn
%O A309018 3,1
%A A309018 _Sergey Perepechko_, Jul 06 2019