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 A008392 #29 May 27 2023 02:09:37
%S A008392 1,73,1405,13237,79459,350683,1240399,3716695,9793891,23301307,
%T A008392 51019255,104285215,201186025,369464785,650284045,1102999717,
%U A008392 1811113021,2889580645,4493676169,6829608673,10167117319,14854273567,21334735555,30167712043,42050906191,57846722311
%N A008392 Crystal ball sequence for A_8 lattice.
%H A008392 T. D. Noe, <a href="/A008392/b008392.txt">Table of n, a(n) for n = 0..1000</a>
%H A008392 J. H. Conway and N. J. A. Sloane, Low-Dimensional Lattices VII: Coordination Sequences, Proc. Royal Soc. London, A453 (1997), 2369-2389 (<a href="http://neilsloane.com/doc/Me220.pdf">pdf</a>).
%H A008392 <a href="/index/Cor#crystal_ball">Index entries for crystal ball sequences</a>
%H A008392 <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (9,-36,84,-126,126,-84,36,-9,1).
%F A008392 a(n) = 143/448*n^8 + 143/112*n^7 + 2431/480*n^6 + 429/40*n^5 + 3355/192*n^4 + 297/16*n^3 + 22079/1680*n^2 + 761/140*n + 1. - _T. D. Noe_, Apr 29 2007
%F A008392 G.f.: (1 +64*x +784*x^2 +3136*x^3 +4900*x^4 +3136*x^5 +784*x^6 +64*x^7 +x^8)/(1-x)^9. - _Colin Barker_, Mar 16 2012
%t A008392 LinearRecurrence[{9,-36,84,-126,126,-84,36,-9,1}, {1,73,1405,13237, 79459,350683,1240399,3716695,9793891}, 41] (* _G. C. Greubel_, May 26 2023 *)
%o A008392 (Magma) [1 +n*(n+1)*(36528+51788*n+72952*n^2+44473*n^3+27599*n^4 +6435*n^5+2145*n^6)/6720: n in [0..40]]; // _G. C. Greubel_, May 26 2023
%o A008392 (SageMath) [1+n*(n+1)*(36528+51788*n+72952*n^2+44473*n^3+27599*n^4 +6435*n^5+2145*n^6)/6720 for n in range(41)] # _G. C. Greubel_, May 26 2023
%K A008392 nonn,easy
%O A008392 0,2
%A A008392 _N. J. A. Sloane_ and _J. H. Conway_