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 A053444 #9 Nov 08 2018 21:11:52
%S A053444 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,7,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,7,
%T A053444 3,3,3,3,3,3,3,3,11,3,3,3,3,3,3,3,3,7,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,
%U A053444 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,11,3,3,7,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3
%N A053444 x^2 + y^2 mod A053443(n) does not take on value a(n).
%H A053444 Antti Karttunen, <a href="/A053444/b053444.txt">Table of n, a(n) for n = 1..5000</a>
%o A053444 (PARI)
%o A053444 A053444list(up_to) = { my(v=vector(up_to),t,n=1,i=0); while(i<up_to,my(u=vector(n),ind); for(x=0, (n+1)\2, for(y=0, x, u[((x^2+y^2)%n)+1]=1)); if(0==vecmin(u,&ind), i++; v[i] = ind-1); n++); (v); };
%o A053444 v053444 = A053444list(up_to);
%o A053444 A053444(n) = v053444[n]; \\ _Antti Karttunen_, Nov 07 2018
%Y A053444 Cf. A053443.
%K A053444 nonn
%O A053444 1,1
%A A053444 _David W. Wilson_