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 A353803 #8 May 15 2022 12:34:14
%S A353803 0,0,0,0,0,0,0,0,0,9,0,0,0,0,24,0,0,0,0,0,42,21,0,0,0,0,0,0,0,141,0,0,
%T A353803 72,36,56,0,0,0,48,54,0,168,0,0,0,45,0,0,0,0,78,21,0,0,141,0,108,54,0,
%U A353803 192,0,0,0,0,64,381,0,0,168,317,0,0,0,0,0,0,168,192,0,0,0,72,0,336,188,0,144,126,0,126,112
%N A353803 a(n) = Product_{p^e||n} sigma(sigma(p^e)) - sigma(sigma(n)), where n = Product_{p^e||n}, with each p^e the maximal power of prime p that divides n.
%H A353803 Antti Karttunen, <a href="/A353803/b353803.txt">Table of n, a(n) for n = 1..20000</a>
%H A353803 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A353803 a(n) = A353802(n) - A051027(n).
%o A353803 (PARI)
%o A353803 A051027(n) = sigma(sigma(n));
%o A353803 A353803(n) = { my(f = factor(n)); (prod(k=1, #f~, A051027(f[k, 1]^f[k, 2])) - A051027(n)); };
%Y A353803 Cf. A000203, A051027, A353802, A353804, A353805, A353806.
%Y A353803 Cf. A336547 (positions of 0's), A336548 (positions of terms > 0).
%Y A353803 Cf. also A353753.
%K A353803 nonn
%O A353803 1,10
%A A353803 _Antti Karttunen_, May 08 2022