%I #10 Jul 28 2020 14:02:04
%S 0,0,0,1,0,0,0,3,1,0,0,1,0,0,0,7,0,1,0,1,0,0,0,3,1,0,4,1,0,0,0,15,0,0,
%T 0,6,0,0,0,3,0,0,0,1,1,0,0,7,1,1,0,1,0,4,0,3,0,0,0,1,0,0,1,31,0,0,0,1,
%U 0,0,0,16,0,0,1,1,0,0,0,7,13,0,0,1,0,0,0,3,0,1,0,1,0,0,0,15,0,1,1,8,0,0,0,3,0
%N Sum of proper divisors of {n divided by its largest squarefree divisor}.
%H Antti Karttunen, <a href="/A336567/b336567.txt">Table of n, a(n) for n = 1..16384</a>
%H Antti Karttunen, <a href="/A336567/a336567.txt">Data supplement: n, a(n) computed for n = 1..65537</a>
%F a(n) = A001065(A003557(n)).
%F a(n) = A335341(n) - A003557(n) = A336563(n) / A007947(n).
%o (PARI)
%o A007947(n) = factorback(factorint(n)[, 1]);
%o A057723(n) = { my(r=A007947(n)); (r*sigma(n/r)); };
%o A336563(n) = (A057723(n)-n);
%o A336567(n) = (A336563(n)/A007947(n));
%Y Cf. A000203, A001065, A003557, A007947, A057723, A335341, A336563.
%K nonn
%O 1,8
%A _Antti Karttunen_, Jul 27 2020
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