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 A026040 #29 Nov 04 2024 14:36:44
%S A026040 24,40,64,98,144,204,280,374,488,624,784,970,1184,1428,1704,2014,2360,
%T A026040 2744,3168,3634,4144,4700,5304,5958,6664,7424,8240,9114,10048,11044,
%U A026040 12104,13230,14424,15688,17024,18434,19920,21484,23128,24854,26664
%N A026040 a(n) = dot_product(1,2,...,n)*(4,5,...,n,1,2,3).
%H A026040 Vincenzo Librandi, <a href="/A026040/b026040.txt">Table of n, a(n) for n = 4..1000</a>
%H A026040 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (4,-6,4,-1).
%F A026040 a(n) = n(n^2 - 3n + 14)/3 (n >= 4). - _Emeric Deutsch_, Nov 27 2006
%F A026040 G.f.: x^4*(24 - 56*x + 48*x^2 - 14*x^3)/(1 - x)^4. - _Colin Barker_, Sep 17 2012
%p A026040 a:=n->n*(n^2-3*n+14)/3: seq(a(n),n=4..50); # _Emeric Deutsch_, Nov 27 2006
%t A026040 Table[Range[n].RotateLeft[Range[n],3], {n,4,52}] (* _T. D. Noe_, Nov 07 2006 *)
%t A026040 CoefficientList[Series[(24 - 56 x + 48 x^2 - 14 x^3)/(1 - x)^4, {x, 0, 50}], x] (* _Vincenzo Librandi_, Oct 17 2013 *)
%t A026040 LinearRecurrence[{4,-6,4,-1},{24,40,64,98},60] (* _Harvey P. Dale_, Nov 04 2024 *)
%o A026040 (Magma) [n*(n^2-3*n+14)/3: n in [4..50]]; // _Vincenzo Librandi_, Oct 17 2013
%Y A026040 Column 3 of triangle A094414.
%K A026040 nonn,easy
%O A026040 4,1
%A A026040 _Clark Kimberling_
%E A026040 Corrected by _T. D. Noe_, Nov 07 2006