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%I #9 Feb 16 2019 20:40:07
%S 0,2,2,6,4,0,6,14,12,16,10,24,12,16,12,30,16,36,18,36,28,32,22,48,30,
%T 40,36,0,28,48,30,60,36,52,44,90,36,56,52,80,40,48,42,72,72,64,46,120,
%U 54,90,60,96,52,96,68,112,76,88,58,144,60,88,102,126,80,96,66,120,84,128,70,192,72,112,122,136,92,144,78,184,120,124,82
%N a(n) = sigma(n) - gcd(n*d(n), sigma(n)), where d(n) = number of divisors of n (A000005) and sigma(n) = sum of divisors of n (A000203).
%H Antti Karttunen, <a href="/A324122/b324122.txt">Table of n, a(n) for n = 1..10080</a>
%H Antti Karttunen, <a href="/A324122/a324122.txt">Data supplement: n, a(n) computed for n = 1..117800</a>
%F a(n) = A000203(n) - A324121(n) = A000203(n) - gcd(A000203(n), A038040(n)).
%o (PARI) A324122(n) = (sigma(n) - gcd(sigma(n),n*numdiv(n)));
%Y Cf. A000005, A000203, A038040, A106315, A106316, A324045, A324046, A324047, A324121.
%Y Cf. A001599 (positions of zeros).
%K nonn
%O 1,2
%A _Antti Karttunen_, Feb 15 2019
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