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 A054460 #9 Feb 06 2024 10:17:23
%S A054460 1,9,48,204,765,2649,8680,27312,83313,247985,723624,2077164,5880797,
%T A054460 16454865,45577200,125130432,340882113,922265721,2479938368,
%U A054460 6631802220,17646603933,46744464745,123314065944,324085913136,848801213425
%N A054460 A001333(n), n >= 1, convolved twice with itself.
%C A054460 a(n) = A054458(n+2,2) (third column of convolution triangle).
%H A054460 <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (6,-9,-4,9,6,1)
%F A054460 a(n) = (n+1)*(LP2(n+1)+2*LP2(n)+LP2(n-1))/8, n >= 1, LP2(n) = A054459(n), a(0) = 1.
%F A054460 a(n) = (n+1)*((10*n+11)*LP(n)+(4*n+5)*LP(n-1))/16, n >= 1, LP(n) = A001333(n+1).
%F A054460 G.f.: ((1+x)/(1-2*x-x^2))^3.
%F A054460 a(n) = +6*a(n-1) -9*a(n-2) -4*a(n-3) +9*a(n-4) +6*a(n-5) +a(n-6). - _R. J. Mathar_, Feb 05 2024
%t A054460 LinearRecurrence[{6, -9, -4, 9, 6, 1}, {1, 9, 48, 204, 765, 2649}, 30] (* _Paolo Xausa_, Feb 06 2024 *)
%Y A054460 Cf. A054458, A054459, A001333, A002203.
%K A054460 easy,nonn
%O A054460 0,2
%A A054460 _Wolfdieter Lang_, Apr 26 2000