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a(n) = sigma(n) / gcd(sigma(n), n+A003415(n)), where A003415 is the arithmetic derivative, and sigma is the sum of divisors of n.
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%I #9 May 24 2021 00:45:26

%S 1,1,1,7,1,12,1,3,13,18,1,1,1,24,24,31,1,1,1,21,32,36,1,15,31,42,20,

%T 14,1,72,1,9,48,54,48,91,1,60,56,5,1,96,1,21,13,72,1,31,19,93,72,49,1,

%U 8,72,30,80,90,1,21,1,96,52,127,84,144,1,9,96,48,1,65,1,114,62,35,96,168,1,93,121,126,1,14,108

%N a(n) = sigma(n) / gcd(sigma(n), n+A003415(n)), where A003415 is the arithmetic derivative, and sigma is the sum of divisors of n.

%H Antti Karttunen, <a href="/A343227/b343227.txt">Table of n, a(n) for n = 1..16384</a>

%H Antti Karttunen, <a href="/A343227/a343227.txt">Data supplement: n, a(n) computed for n = 1..65537</a>

%H <a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>

%F a(n) = A000203(n) / A343226(n) = A000203(n) / gcd(A000203(n), n+A003415(n))

%Y Cf. A000203, A003415, A129283, A343226.

%K nonn

%O 1,4

%A _Antti Karttunen_, Apr 15 2021