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 A353804 #8 May 09 2022 11:02:52
%S A353804 1,4,7,8,12,28,15,24,14,3,28,56,24,60,12,32,39,56,42,96,21,7,60,168,
%T A353804 32,96,90,120,72,3,63,104,4,12,4,112,60,168,24,18,96,84,84,224,168,15,
%U A353804 124,224,80,128,39,3,120,360,3,360,6,18,168,96,96,252,210,128,32,1,126,312,84,1,195,336,114,240,224,336
%N A353804 Greatest common divisor of sigma(sigma(n)) and Product_{p^e||n} sigma(sigma(p^e)), where n = Product_{p^e||n}, with each p^e the maximal power of prime p that divides n.
%H A353804 Antti Karttunen, <a href="/A353804/b353804.txt">Table of n, a(n) for n = 1..20000</a>
%H A353804 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A353804 a(n) = gcd(A051027(n), A353802(n)) = gcd(A051027(n), A353803(n)) = gcd(A353802(n), A353803(n)).
%o A353804 (PARI)
%o A353804 A051027(n) = sigma(sigma(n));
%o A353804 A353804(n) = { my(f = factor(n)); gcd(A051027(n), prod(k=1, #f~, A051027(f[k, 1]^f[k, 2]))); };
%Y A353804 Cf. A000203, A051027, A353802, A353803, A353805, A353806.
%Y A353804 Cf. also A353754.
%K A353804 nonn,look
%O A353804 1,2
%A A353804 _Antti Karttunen_, May 08 2022