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 A225523 #7 May 10 2013 12:25:28
%S A225523 1,1,3,5,9,11,17,21,27,33,39,43,53,59,69,79,89,97,107,117,131,143,157,
%T A225523 167,183,195,209,223,237,249,269,283,301,317,335,353,373,389,409,427,
%U A225523 449,465,491,509,535,557,581,603,631,657,679
%N A225523 Number of distinct products i*j over all pairs (i,j) with |i| + |j| <= n.
%C A225523 This sequence is in reply to an extension request made in A100449.
%H A225523 Robert Price, <a href="/A225523/b225523.txt">Table of n, a(n) for n = 0..400</a>
%t A225523 f[n_]:=Length[Complement[Union[Flatten[Table[If[Abs[i]+Abs[j]<=n,{i*j}],{i,-n,n},{j,-n,n}],1]],{Null}]]; Table[f[n],{n,0,100}]
%Y A225523 Cf. A018805, A027430, A100448, A100449, A100450, A213207.
%K A225523 nonn,easy
%O A225523 0,3
%A A225523 _Robert Price_, May 09 2013