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 A172163 #18 Apr 25 2022 08:02:29
%S A172163 0,0,10,1020,103030,10307040,1030814050,103082025060,10308214641070,
%T A172163 1030821549763080,103082156348992090,10308215646124529100,
%U A172163 1030821564770799275110,103082156478507926931120,10308215647869324982098130,1030821564787110934730377140
%N A172163 a(n) = ( A165155(n) - A165154(n) )/2.
%H A172163 Colin Barker, <a href="/A172163/b172163.txt">Table of n, a(n) for n = 0..501</a>
%H A172163 <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (102,-101,-9900).
%F A172163 a(n) = 10^(2*n+1)/9701 - 11^n/178 + (-9)^n/218. [_Bruno Berselli_, Oct 02 2015]
%F A172163 From _Colin Barker_, Oct 02 2015: (Start)
%F A172163 a(n) = 102*a(n-1) - 101*a(n-2) - 9900*a(n-3) for n>2.
%F A172163 G.f.: 10*x^2 / ((1+9*x)*(1-11*x)*(1-100*x)).
%F A172163 (End)
%t A172163 Table[10^(2 n + 1)/9701 - 11^n/178 + (-9)^n/218, {n, 0, 20}] (* _Bruno Berselli_, Oct 02 2015 *)
%t A172163 LinearRecurrence[{102,-101,-9900},{0,0,10},20] (* _Harvey P. Dale_, Aug 17 2021 *)
%o A172163 (PARI) concat([0,0], Vec(10*x^2/((9*x+1)*(11*x-1)*(100*x-1)) + O(x^30))) \\ _Colin Barker_, Oct 02 2015
%o A172163 (SageMath) [(89*(-9)^n + 2*10^(2*n+1) - 109*11^n)/19402 for n in (0..50)] # _G. C. Greubel_, Apr 24 2022
%Y A172163 Cf. A162741, A162849, A165154, A165155, A172162.
%K A172163 nonn,easy
%O A172163 0,3
%A A172163 _Mark Dols_, Jan 27 2010
%E A172163 a(0)=0 and more terms added by _Bruno Berselli_, Oct 02 2015