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a(n) = Sum_{d|n} [moebius(n/d) > 0]*(sigma(d)-d).
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%I #7 Aug 27 2018 22:29:49

%S 0,1,1,3,1,6,1,7,4,8,1,17,1,10,9,15,1,22,1,23,11,14,1,39,6,16,13,29,1,

%T 45,1,31,15,20,13,61,1,22,17,53,1,57,1,41,34,26,1,83,8,44,21,47,1,70,

%U 17,67,23,32,1,125,1,34,42,63,19,81,1,59,27,77,1,139,1,40,50,65,19,93,1,113,40,44,1,159,23,46,33,95,1,163,21

%N a(n) = Sum_{d|n} [moebius(n/d) > 0]*(sigma(d)-d).

%H Antti Karttunen, <a href="/A318325/b318325.txt">Table of n, a(n) for n = 1..65537</a>

%F a(n) = Sum_{d|n} [A008683(n/d) == 1]*A001065(d).

%F a(n) = A051953(n) + A318326(n).

%F a(n) = A291784(n) - A318441(n).

%o (PARI) A318325(n) = sumdiv(n,d,(1==moebius(n/d))*(sigma(d)-d));

%Y Cf. A001065, A051953, A291784, A318320, A318326, A318441.

%K nonn

%O 1,4

%A _Antti Karttunen_, Aug 26 2018