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Multiplicative with a(p^e) = sigma(sigma(p^e)).
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%I #14 May 09 2022 11:03:25

%S 1,4,7,8,12,28,15,24,14,48,28,56,24,60,84,32,39,56,42,96,105,112,60,

%T 168,32,96,90,120,72,336,63,104,196,156,180,112,60,168,168,288,96,420,

%U 84,224,168,240,124,224,80,128,273,192,120,360,336,360,294,288,168,672,96,252,210,128,288,784,126,312,420,720

%N Multiplicative with a(p^e) = sigma(sigma(p^e)).

%H Antti Karttunen, <a href="/A353802/b353802.txt">Table of n, a(n) for n = 1..20000</a>

%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>

%F a(n) = 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.

%F a(n) = A051027(n) + A353803(n).

%F a(n) = A353804(n) * A353806(n).

%o (PARI)

%o A051027(n) = sigma(sigma(n));

%o A353802(n) = { my(f = factor(n)); prod(k=1, #f~, A051027(f[k, 1]^f[k, 2])); };

%Y Cf. A000203, A051027, A353803, A353804, A353805, A353806.

%Y Cf. also A336547, A336548, A353752.

%K nonn,mult

%O 1,2

%A _Antti Karttunen_, May 08 2022