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 A225526 #12 Aug 02 2019 05:27:34
%S A225526 1,1,3,5,7,11,13,17,21,27,31,39,43,51,57,63,69,81,87,99,107,117,125,
%T A225526 139,147,159,169,183,195,215,223,241,257,273,287,305,315,339,353,371,
%U A225526 383,407,419,443,461,479,497,523,539,567,585
%N A225526 Number of distinct products i*j over all pairs (i,j) with |i| + |j| <= n and gcd(i,j) <= 1.
%C A225526 This sequence is in reply to an extension request made in A100449.
%C A225526 Note that gcd(0,m) = m for any m.
%H A225526 Robert Price, <a href="/A225526/b225526.txt">Table of n, a(n) for n = 0..400</a>
%t A225526 f[n_]:=Length[Complement[Union[Flatten[Table[If[Abs[i]+Abs[j]<=n&&GCD[i,j]<=1, {i*j}], {i, -n, n}, {j, -n, n}], 1]], {Null}]]; Table[f[n], {n, 0, 100}]
%Y A225526 Cf. A018805, A027430, A100448, A100449, A100450, A213208.
%K A225526 nonn,easy
%O A225526 0,3
%A A225526 _Robert Price_, May 09 2013