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 A011926 #22 Jul 08 2025 02:42:48
%S A011926 0,0,0,0,1,7,22,52,105,189,315,495,742,1072,1501,2047,2730,3570,4590,
%T A011926 5814,7267,8977,10972,13282,15939,18975,22425,26325,30712,35626,41107,
%U A011926 47197,53940,61380,69564,78540
%N A011926 a(n) = floor(n*(n-1)*(n-2)*(n-3)/16).
%H A011926 <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (5,-10,10,-6,6,-10,10,-5,1).
%F A011926 From _R. J. Mathar_, Apr 15 2010: (Start)
%F A011926 G.f.: x^4*(x^4+1+2*x-3*x^2+2*x^3) / ((1-x)^5*(x^4+1) ).
%F A011926 a(n) = +5*a(n-1) -10*a(n-2) +10*a(n-3) -6*a(n-4) +6*a(n-5) -10*a(n-6) +10*a(n-7) -5*a(n-8) +a(n-9). (End)
%t A011926 Table[Floor[(n(n-1)(n-2)(n-3))/16],{n,0,40}] (* or *) LinearRecurrence[{5,-10,10,-6,6,-10,10,-5,1},{0,0,0,0,1,7,22,52,105},40] (* _Harvey P. Dale_, Dec 16 2024 *)
%o A011926 (Magma) [Floor(n*(n-1)*(n-2)*(n-3)/16) : n in [0..100]]; // _Wesley Ivan Hurt_, Apr 20 2021
%K A011926 nonn,easy
%O A011926 0,6
%A A011926 _N. J. A. Sloane_