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A331750 a(n) = A048675(sigma(n)).

%I A331750 #11 Feb 08 2020 20:44:56
%S A331750 0,2,2,8,3,4,3,6,32,5,4,10,9,5,5,1024,5,34,6,11,5,6,5,8,1024,11,7,11,
%T A331750 7,7,5,12,6,7,6,40,129,8,11,9,11,7,18,12,35,7,6,1026,130,1026,7,17,7,
%U A331750 9,7,9,8,9,8,13,1025,7,35,1073741824,12,8,66,13,7,8,7,38,2049,131,1026,14,7,13,8,1027,32,13,12,13,8,20,9
%N A331750 a(n) = A048675(sigma(n)).
%H A331750 Antti Karttunen, <a href="/A331750/b331750.txt">Table of n, a(n) for n = 1..10000</a>
%H A331750 <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>
%F A331750 a(n) = A048675(A000203(n)).
%F A331750 Additive with a(p^e) = A048675(sigma(p^e)) = A048675(1 + p + p^2 + ... + p^e).
%t A331750 {0}~Join~Array[Total@ Map[#[[-1]]*2^(PrimePi[#[[1]]] - 1) &, FactorInteger@ DivisorSigma[1, #]] &, 86, 2] (* _Michael De Vlieger_, Feb 08 2020, after _Jean-François Alcover_ at A048675 *)
%o A331750 (PARI)
%o A331750 A048675(n) = { my(f = factor(n)); sum(k=1, #f~, f[k, 2]*2^primepi(f[k, 1]))/2; };
%o A331750 A331750(n) = A048675(sigma(n));
%Y A331750 Cf. A000203, A048675, A324573, A331751.
%K A331750 nonn
%O A331750 1,2
%A A331750 _Antti Karttunen_, Feb 05 2020