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 A173785 #18 Apr 20 2024 11:35:00
%S A173785 2,2,18,98,338,882,1922,3698,6498,10658,16562,24642,35378,49298,66978,
%T A173785 89042,116162,149058,188498,235298,290322,354482,428738,514098,611618,
%U A173785 722402,847602,988418,1146098,1321938,1517282,1733522,1972098,2234498
%N A173785 Expansion of 2*(1 -4*x +14*x^2 +4*x^3 +9*x^4)/(1-x)^5.
%D A173785 Clark Kimberling, Complementary Equations, Journal of Integer Sequences, Vol. 10 (2007), Article 07.1.4.
%H A173785 G. C. Greubel, <a href="/A173785/b173785.txt">Table of n, a(n) for n = 0..1000</a>
%H A173785 Clark Kimberling, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL10/Kimberling/kimberling26.html">Complementary Equations</a>, Journal of Integer Sequences, Vol. 10 (2007), Article 07.1.4.
%H A173785 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (5,-10,10,-5,1).
%F A173785 G.f.: 2*(1 -4*x +14*x^2 +4*x^3 +9*x^4)/(1-x)^5.
%F A173785 a(n) = 2*(n^2 - n + 1)^2.
%F A173785 a(n) = 2*A058031(n).
%F A173785 E.g.f.: 2*(1 + 4*x^2 + 4*x^3 + x^4)*exp(x). - _G. C. Greubel_, Jul 07 2021
%p A173785 a:= n-> 2*(n^2-n+1)^2:
%p A173785 seq (a(n), n=0..40);
%t A173785 Table[2*(1-n+n^2)^2, {n,0,40}] (* _G. C. Greubel_, Jul 07 2021 *)
%t A173785 LinearRecurrence[{5,-10,10,-5,1},{2,2,18,98,338},50] (* _Harvey P. Dale_, Apr 20 2024 *)
%o A173785 (Sage) [2*(1-n+n^2)^2 for n in (0..40)] # _G. C. Greubel_, Jul 07 2021
%o A173785 (PARI) a(n)=2*(n^2-n+1)^2 \\ _Charles R Greathouse IV_, Oct 21 2022
%Y A173785 Cf. A058031.
%K A173785 nonn,easy
%O A173785 0,1
%A A173785 _Michel Lagneau_, Feb 24 2010
%E A173785 Edited by _Alois P. Heinz_, Feb 16 2012