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 A332221 #10 Feb 13 2020 20:15:48
%S A332221 0,2,3,8,5,11,7,10,32,13,11,35,17,23,23,1024,13,66,19,37,31,27,23,43,
%T A332221 1024,37,39,71,21,55,31,38,47,29,47,72,257,43,71,45,37,95,67,75,133,
%U A332221 55,47,4099,258,2050,55,49,29,87,55,87,79,45,43,151,2049,95,263,1073741824,75,111,259,77,95,111,55,138,4097,517,4099,83
%N A332221 a(n) = A156552(sigma(n)).
%H A332221 Antti Karttunen, <a href="/A332221/b332221.txt">Table of n, a(n) for n = 1..8192</a>
%H A332221 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A332221 a(n) = A156552(A000203(n)).
%F A332221 A000120(a(n)) = A058063(n).
%t A332221 Array[Floor@ Total@ Flatten@ MapIndexed[#1 2^(#2 - 1) &, Flatten[Table[2^(PrimePi@ #1 - 1), {#2}] & @@@ FactorInteger@ DivisorSigma[1, #]]] &, 76] (* _Michael De Vlieger_, Feb 12 2020 *)
%o A332221 (PARI)
%o A332221 A156552(n) = {my(f = factor(n), p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res}; \\ From A156552
%o A332221 A332221(n) = A156552(sigma(n));
%Y A332221 Cf. A000203, A156552, A058063, A332216 (fixed points), A332218, A332222.
%K A332221 nonn
%O A332221 1,2
%A A332221 _Antti Karttunen_, Feb 12 2020