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 A070803 #14 Sep 08 2022 08:45:06
%S A070803 0,2,2,4,3,5,4,6,6,7,5,9,6,9,9,11,7,12,8,13,11,11,9,17,11,13,12,16,10,
%T A070803 20,11,18,15,16,15,24,12,17,16,24,13,24,14,23,21,20,15,30,16,24,20,25,
%U A070803 16,30,20,30,22,24,17,39,18,24,27,31,23,34,19,30,24,34,20,44,21,30,30
%N A070803 Number of primes not exceeding sum of divisors of n.
%H A070803 Vincenzo Librandi, <a href="/A070803/b070803.txt">Table of n, a(n) for n = 1..5000</a>
%F A070803 a(n) = A000720(A000203(n)) = pi(sigma(n)).
%e A070803 n=50: sigma(50) = 93, pi(93) = 24 = a(50).
%t A070803 Table[PrimePi[DivisorSigma[1, n]], {n, 1, 256}]
%o A070803 (Sage) [prime_pi(sigma(n,1)) for n in range(1, 76)] # - _Zerinvary Lajos_, Jun 06 2009
%o A070803 (PARI) A070803(n) = primepi(sigma(n)) \\ _Michael B. Porter_, Jan 28 2010
%o A070803 (Magma) [#PrimesUpTo(SumOfDivisors(n)): n in [1..100]]; // _Vincenzo Librandi_, Feb 06 2017
%Y A070803 Cf. A007818, A000203, A000720, A070800-A070804.
%K A070803 easy,nonn
%O A070803 1,2
%A A070803 _Labos Elemer_, May 08 2002