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 A067196 #11 Mar 18 2017 19:20:10
%S A067196 1,6,142,154,157,167,168,169,209,213,214,231,232,235,236,238,239,240,
%T A067196 242,243,244,245,247,248,251,252,257,259,260,261,263,264,266,269,270,
%U A067196 278,279,280,301,318,362,363,364,366,367,368,369,371,372,391,392,402
%N A067196 Numbers n such that M(n) = Sum_{i=1..n} mu(phi(i)) where M(n) is the Mertens function A002321(n).
%t A067196 mQ[n_]:=Sum[MoebiusMu[i],{i,n}]==Sum[MoebiusMu[EulerPhi[i]],{i,n}]; Select[Range[405],mQ[#] &] (* _Jayanta Basu_, May 22 2013 *)
%K A067196 nonn
%O A067196 1,2
%A A067196 _Benoit Cloitre_, Feb 19 2002