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 A087122 #13 Sep 20 2019 07:54:25
%S A087122 1,3,5,12,9,15,13,32,45,27,21,60,25,39,45,128,33,135,37,108,65,63,45,
%T A087122 160,225,75,189,156,57,135,61,320,105,99,117,540,73,111,125,288,81,
%U A087122 195,85,252,405,135,93,640,637,675,165,300,105,567,189,416,185,171,117,540,121,183,585,1280,225,315,133,396,225,351
%N A087122 a(n) is the number of non-congruent solutions to x^2*y^2 == 0 (mod n).
%H A087122 Andrew Howroyd, <a href="/A087122/b087122.txt">Table of n, a(n) for n = 1..10000</a>
%F A087122 Multiplicative with a(p^e) = p^(e + floor(e/2) - 1)*((p-1)*ceiling(e/2) + p). - _Andrew Howroyd_, Jul 15 2018
%t A087122 a[n_] := Product[{p, e} = pe; p^(e+Floor[e/2]-1)((p-1) Ceiling[e/2]+p), {pe, FactorInteger[n]}];
%t A087122 a /@ Range[1, 100] (* _Jean-François Alcover_, Sep 20 2019 *)
%o A087122 (PARI) a(n)={my(f=factor(n)); prod(i=1, #f~, my(p=f[i,1], e=f[i,2]); p^(e + e\2 - 1)*((p-1)*((e+1)\2) + p))} \\ _Andrew Howroyd_, Jul 15 2018
%Y A087122 Cf. A078430, A018804.
%K A087122 mult,nonn
%O A087122 1,2
%A A087122 Yuval Dekel (dekelyuval(AT)hotmail.com), Oct 18 2003