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 A265135 #10 Dec 26 2015 18:43:34
%S A265135 81,106,181,211,256,276,331,361,381,406,456,471,531,556,601,606,616,
%T A265135 631,666,681,706,718,731,781,786,856,861,871,906,931,939,956,981,991,
%U A265135 1051,1056,1126,1131,1156,1186,1206,1231,1281,1296,1341,1381,1446,1456
%N A265135 Numbers that are the sum of two distinct nonzero triangular numbers in more than two ways.
%t A265135 r = 1456; lst = Table[0, {r}]; lim = Floor[Sqrt[8*r - 7]]; Do[num = (i^2 + i)/2 + (j^2 + j)/2; If[num <= r, lst[[num]]++], {i, lim}, {j, i - 1}]; Flatten@Position[lst, n_ /; n > 2]
%t A265135 Module[{nn=60,trnos},trnos=Accumulate[Range[nn]];Select[Sort[Flatten[ Table[ PositionIndex[Counts[Total/@Subsets[trnos,{2}]]][i],{i,3,nn}]]], #<= Last[trnos]&]] (* The program uses the PositionIndex and Counts functions from Mathematica version 10 *) (* _Harvey P. Dale_, Dec 26 2015 *)
%Y A265135 Cf. A000217, A051533, A260647, A265140 (exactly one way), A262749 (more than one way), A265134 (exactly two ways), A265136 (exactly three ways), A265137 (more than three ways), A265138 (exactly four ways).
%K A265135 nonn
%O A265135 1,1
%A A265135 _Arkadiusz Wesolowski_, Dec 02 2015