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 A213033 #13 Jul 25 2015 10:37:42
%S A213033 0,0,0,3,8,10,36,42,64,108,150,165,288,312,392,525,640,680,972,1026,
%T A213033 1200,1470,1694,1771,2304,2400,2704,3159,3528,3654,4500,4650,5120,
%U A213033 5808,6358,6545,7776,7992,8664,9633,10400,10660,12348,12642,13552
%N A213033 n*[n/2]*[n/3], where [] = floor.
%H A213033 <a href="/index/Rec#order_17">Index entries for linear recurrences with constant coefficients</a>, signature (0, 1, 1, 0, -1, 2, 0, -2, -2, 0, 2, -1, 0, 1, 1, 0, -1).
%F A213033 a(n) = a(n-2)+a(n-3)-a(n-5)+2*a(n-6)-2*a(n-8)+2*a(n-11)-a(n-12)+a(n-14)+a(n-15)-a(n-17).
%F A213033 G.f.: (3*x^3 + 8*x^4 + 7*x^5 + 25*x^6 + 24*x^7 + 21*x^8 + 32*x^9 + 38*x^10 + 15*x^11 + 22*x^12 + 13*x^13 + 5*x^14 + 2*x^15 + x^16)/(1 - x^2 - x^3 + x^5 - 2*x^6 + 2*x^8 + 2*x^9 - 2*x^11 + x^12 - x^14 - x^15 + x^17).
%t A213033 a[n_] := n*Floor[n/2]*Floor[n/3]
%t A213033 Table[a[n], {n, 0, 90}] (* A213033 *)
%t A213033 LinearRecurrence[{0, 1, 1, 0, -1, 2, 0, -2, -2, 0, 2, -1, 0, 1, 1, 0, -1}, {0, 0, 0, 3, 8, 10, 36, 42, 64, 108, 150, 165, 288, 312, 392, 525, 640}, 60]
%Y A213033 Cf. A242669.
%K A213033 nonn,easy
%O A213033 0,4
%A A213033 _Clark Kimberling_, Jun 05 2012