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 A073464 #16 Sep 08 2022 08:45:06 %S A073464 0,0,0,1,2,2,0,2,0,0,4,0,0,2,2,2,6,2,0,4,2,4,8,2,3,0,3,8,8,8,5,9,5,2, %T A073464 1,0,6,0,4,1,12,0,6,10,8,1,1,12,5,2,9,4,2,8,8,4,12,7,16,6,12,0,14,12, %U A073464 2,9,13,6,5,10,4,9,15,19,15,18,3,12,10,10,18,13,1,18,19,10,17,16,0,0,20,12 %N A073464 a(n) = phi(n) mod PrimePi(n). %H A073464 Vincenzo Librandi, <a href="/A073464/b073464.txt">Table of n, a(n) for n = 2..10000</a> %F A073464 a(n) = A000010(n) mod A000720(n). %t A073464 a(n)=Table[Mod[EulerPhi[w], PrimePi[w]], {w, 2, 1000}] %o A073464 (PARI) a(n) = eulerphi(n) % primepi(n); \\ _Michel Marcus_, Dec 11 2018 %o A073464 (Magma) [EulerPhi(n) mod #PrimesUpTo(n): n in [2..100]]; // _Vincenzo Librandi_, Dec 11 2018 %Y A073464 Cf. A000010, A000720. %Y A073464 Cf. A037228, A037171. %Y A073464 Cf. A073453, A073454, A073455, A073456, A073457, A072530, A072531, A073461, A073461. %K A073464 nonn %O A073464 2,5 %A A073464 _Labos Elemer_, Aug 02 2002