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 A081280 #16 Aug 23 2024 20:39:30
%S A081280 1,10,69,398,2057,9858,44685,194022,813969,3319866,13224789,51635070,
%T A081280 198148761,749016882,2794021533,10300389462,37575535905,135782112618,
%U A081280 486470994021,1729358969454,6104068084521,21404982017250,74609825192109
%N A081280 Binomial transform of Chebyshev coefficients A006974.
%H A081280 Vincenzo Librandi, <a href="/A081280/b081280.txt">Table of n, a(n) for n = 0..1000</a>
%H A081280 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (15,-90,270,-405,243).
%F A081280 a(n) = (n^4+24*n^3+164*n^2+378*n+243) * 3^(n-5).
%F A081280 a(n) = 15*a(n-1) -90*a(n-2) +270a*(n-3) -405*a(n-4) +243*a(n-5).
%F A081280 G.f.: (1-2*x)*(1-x)^3/(1-3*x)^5.
%t A081280 CoefficientList[Series[(1 - 2 x) (1 - x)^3 / (1 - 3 x)^5, {x, 0, 40}], x] (* _Vincenzo Librandi_, Aug 07 2013 *)
%t A081280 LinearRecurrence[{15,-90,270,-405,243},{1,10,69,398,2057},30] (* _Harvey P. Dale_, May 05 2019 *)
%o A081280 (Magma) [(n^4+24*n^3+164*n^2+378*n+243)*3^(n-5): n in [0..25]]; // _Vincenzo Librandi_, Aug 07 2013
%Y A081280 Cf. A007051, A006234, A081279, A081281.
%K A081280 easy,nonn
%O A081280 0,2
%A A081280 _Paul Barry_, Mar 16 2003