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 A072548 #19 Sep 08 2022 08:45:06
%S A072548 0,0,1,0,0,0,3,1,2,2,3,2,0,0,1,4,4,4,2,0,4,6,6,4,6,4,2,0,2,10,8,4,10,
%T A072548 4,3,2,0,8,6,3,5,2,0,8,2,3,4,12,3,12,8,6,8,8,8,0,10,9,15,8,6,14,1,12,
%U A072548 0,11,12,1,11,12,15,11,9,19,14,12,0,14,10,11,16,15,17,16,17,5,19,18,18
%N A072548 a(n) = sigma(n) mod PrimePi(n).
%H A072548 Michael De Vlieger, <a href="/A072548/b072548.txt">Table of n, a(n) for n = 2..10000</a>
%F A072548 a(n) = A000203(n) mod A000720(n).
%p A072548 with(numtheory): seq(modp(sigma(n),pi(n)),n=2..100); # _Muniru A Asiru_, Dec 10 2018
%t A072548 Table[Mod[DivisorSigma[1, w], PrimePi[w]], {w, 1, 128}]
%o A072548 (PARI) a(n) = sigma(n) % primepi(n); \\ _Michel Marcus_, Dec 10 2018
%o A072548 (Magma) [SumOfDivisors(n) mod (#PrimesUpTo(n)): n in [2..100]]; // _Vincenzo Librandi_, Dec 10 2018
%Y A072548 Cf. A000203, A000720, A073321, A073322, A073323, A073324.
%K A072548 nonn
%O A072548 2,7
%A A072548 _Labos Elemer_, Aug 05 2002