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 A003771 #23 Sep 10 2023 21:04:47 %S A003771 3,30,198,1326,8886,59550,399078,2674446,17922966,120111870,804937158, %T A003771 5394336366,36150480246,242264688990,1623551862438,10880333659086, %U A003771 72915231888726,488645955902910,3274691227542918,21945546680994606,147069444311876406,985595016821145630 %N A003771 Number of Hamiltonian cycles in K_4 X P_n. %H A003771 Frans J. Faase, <a href="http://www.iwriteiam.nl/Cpaper.zip">On the number of specific spanning subgraphs of the graphs G X P_n</a>, Preliminary version of paper that appeared in Ars Combin. 49 (1998), 129-154. %H A003771 Frans J. Faase, <a href="http://www.iwriteiam.nl/counting.html">Counting Hamiltonian cycles in product graphs</a> %H A003771 Frans J. Faase, <a href="http://www.iwriteiam.nl/Cresults.html">Results from the counting program</a> %H A003771 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (7,-2). %F A003771 a(n) = 7*a(n-1) - 2*a(n-2), n>3. %F A003771 G.f.: 3*x*(1+3*x-2*x^2)/(1-7*x+2*x^2). - _R. J. Mathar_, Dec 16 2008 %K A003771 nonn,easy %O A003771 1,1 %A A003771 _Frans J. Faase_ %E A003771 More terms from _Stefano Spezia_, May 13 2023