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 A076363 #11 Jul 09 2018 03:09:30
%S A076363 1,1,1,1,3,1,5,3,4,2,9,2,11,4,5,7,15,4,17,6,9,8,21,6,18,10,16,10,27,5,
%T A076363 29,15,17,14,21,10,35,16,21,14,39,9,41,18,21,20,45,14,40,18,29,22,51,
%U A076363 16,37,22,33,26,57,13,59,28,33,31,45,17,65,30,41,21,69,22,71,34,37,34
%N A076363 a(n) = A000010(n) - A061498(n).
%o A076363 (PARI) a061498(n) = {my(va = select(x->(gcd(n, x)==1), [1..n])); vd = vector(#va-1, k, va[k+1] - va[k]); #Set(vd);}
%o A076363 a(n) = eulerphi(n) - a061498(n); \\ _Michel Marcus_, Jul 08 2018
%Y A076363 Cf. A000010, A061498.
%K A076363 nonn
%O A076363 1,5
%A A076363 _Labos Elemer_, Oct 09 2002