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 A103504 #13 Sep 23 2014 14:27:37
%S A103504 123,1298,4929,9516,10066,14192,15830,15887,17854,20007,23394,24574,
%T A103504 27441,31932,33377,33381,33933,35594,35978,37075,40139,40931,41205,
%U A103504 43573,45147,47661,47749,48286,48444,48941,50580,51659,52377,59375,61260,61726,62465,63063
%N A103504 Integers that do not appear in A103502.
%C A103504 For n>1873, A103502(n)>123 and for n>27763, A103502(n)>1298. - _Michel Marcus_, Feb 06 2014
%H A103504 Hiroaki Yamanouchi, <a href="/A103504/b103504.txt">Table of n, a(n) for n = 1..3804</a>
%t A103504 Restop = Function[n, pp = Prime[Range[PrimePi[n]]]; Sum[n/pp[[k]] - Floor[n/pp[[k]]], {k, 1, Length[pp]}]]; oops = Floor[Map[Restop, Range[1, 30000]]]; Complement[Range[Max[oops]], Union[oops]]
%t A103504 f[n_] := Floor[Plus @@ FractionalPart[n / Table[ Prime[i], {i, PrimePi[n]}]]]; Do[ a = f[n]; If[ Position[t, a] == {}, AppendTo[t, a]], {n, 81900}]; Complement[ Range[ Sort[t][[ -1]]], t] (* _Robert G. Wilson v_, Feb 12 2005 *)
%Y A103504 Cf. A103502.
%K A103504 nonn
%O A103504 1,1
%A A103504 _Carlos Alves_, Feb 08 2005
%E A103504 a(3)-a(38) from _Hiroaki Yamanouchi_, Sep 23 2014