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%I #14 May 18 2021 07:24:43
%S 0,1,4,5,5,16,12,16,16,21,16,44,9,44,44,44,21,60,24,60,80,60,44,112,
%T 31,41,60,112,31,156,80,112,112,81,112,156,21,92,92,156,41,272,48,156,
%U 156,156,112,272,92,123,156,124,81,216,156,272,176,123,92,384,33,272,272,272,124,384,72,216,272,384,156,384,39,101
%N a(n) = A003415(A001615(n)).
%C The first nonsquarefree numbers for which this sequence coincides with A342925 are 868, 920, 952, 4260, 4452, 4692, 5060, 5172, ...
%H Antti Karttunen, <a href="/A344024/b344024.txt">Table of n, a(n) for n = 1..16384</a>
%F a(A005117(n)) = A342925(A005117(n)) for all n.
%t {0}~Join~Array[If[# < 2, 0, # Total[#2/#1 & @@@ FactorInteger[#]]] &[# Product[1 + 1/p, {p, FactorInteger[#][[All, 1]]}] ] &, 73, 2] (* _Michael De Vlieger_, May 16 2021 *)
%o (PARI)
%o A001615(n) = if(1==n,n, my(f=factor(n)); prod(i=1, #f~, f[i, 1]^f[i, 2] + f[i, 1]^(f[i, 2]-1))); \\ After code in A001615
%o A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
%o A344024(n) = A003415(A001615(n));
%Y Cf. A001615, A003415, A005117.
%Y Cf. also A342925.
%K nonn
%O 1,3
%A _Antti Karttunen_, May 09 2021
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