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 A229298 #27 Mar 22 2015 09:52:47
%S A229298 5,54,515,5109,50933,508932,5087994
%N A229298 Number of terms in A228919 less than or equal to 10^n.
%C A229298 0.50801 < lim A229298(n)/10^n = lim A229299(n)/10^n < 0.50966.
%C A229298 Compare with A229299(n)/10^n.
%H A229298 J. M. Grau, A. M. Oller-Marcén, <a href="http://arxiv.org/abs/1304.2678">About the congruence sum_{k=1..n} k^{f(n)} == 0 (mod n)</a>, arXiv:1304.2678 [math.NT], 2013.
%t A229298 fa=FactorInteger; Carlitz[k_,n_] := Mod[n-Sum[If[IntegerQ[k/(fa[n][[i,1]]-1)], n/fa[n][[i, 1]], 0], {i, 1, Length[fa[n]]}], n]; supercar[k_, n_] := If[k == 1 || Mod[k,2] == 0 || Mod[n, 4] > 0, Carlitz[k, n], Mod[Carlitz[k, n] - n/2, n]]; Table[Print[Length@Select[Range[10^n], supercar[#+1,#] == 0 &]], {n, 1, 7}]
%Y A229298 Cf. A191677, A228919, A229299.
%K A229298 nonn,more,hard
%O A229298 1,1
%A A229298 _José María Grau Ribas_, Sep 20 2013