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 A263229 #24 Mar 04 2025 21:43:56
%S A263229 0,-20,128,444,928,1580,2400,3388,4544,5868,7360,9020,10848,12844,
%T A263229 15008,17340,19840,22508,25344,28348,31520,34860,38368,42044,45888,
%U A263229 49900,54080,58428,62944,67628,72480,77500,82688,88044,93568,99260,105120,111148,117344,123708,130240
%N A263229 a(n) = 4*n*(21*n - 26).
%C A263229 For n>=3, a(n) = the hyper-Wiener index of the Jahangir graph J_{4,n}.
%C A263229 See A263228 for more comments.
%H A263229 M. R. Farahani, <a href="https://www.researchgate.net/publication/276059305_Hosoya_Polynomial_of_Jahangir_graphs_J4m_101">Hosoya polynomial and of Jahangir graphs J_{4,m}</a>, Global J. Math, 3 (1), 232-236, 2015.
%H A263229 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (3,-3,1).
%F A263229 G.f.: 4*x*(47*x-5)/(1-x)^3.
%F A263229 a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3).
%p A263229 seq(84*n^2 - 104*n, n=0..40);
%t A263229 Table[4 n (21 n - 26), {n, 0, 40}] (* _Bruno Berselli_, Oct 15 2015 *)
%o A263229 (Magma) [4*n*(21*n-26): n in [0..20]]; // _Vincenzo Librandi_, Oct 15 2015
%o A263229 (PARI) vector(50, n, n--; 4*n*(21*n-26)) \\ _Altug Alkan_, Oct 15 2015
%Y A263229 Cf. A049598, A263226, A263227, A263228, A263231.
%K A263229 sign,easy
%O A263229 0,2
%A A263229 _Emeric Deutsch_, Oct 13 2015