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a(n) = A129283(n) / gcd(sigma(n), A129283(n)), where A129283(n) is the sum of n and its arithmetic derivative.
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%I #10 Jun 30 2021 10:34:16

%S 1,1,1,8,1,11,1,4,15,17,1,1,1,23,23,48,1,1,1,22,31,35,1,17,35,41,27,

%T 15,1,61,1,16,47,53,47,96,1,59,55,6,1,83,1,23,14,71,1,40,21,95,71,54,

%U 1,9,71,37,79,89,1,19,1,95,57,256,83,127,1,10,95,43,1,76,1,113,65,39,95,149,1,128,189,125,1,13,107

%N a(n) = A129283(n) / gcd(sigma(n), A129283(n)), where A129283(n) is the sum of n and its arithmetic derivative.

%H Antti Karttunen, <a href="/A345059/b345059.txt">Table of n, a(n) for n = 1..12800</a>

%H Antti Karttunen, <a href="/A345059/a345059.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) = A129283(n) / A343226(n) = A129283(n) / gcd(A000203, A129283(n)).

%o (PARI)

%o A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));

%o A129283(n) = (n+A003415(n));

%o A345059(n) = { my(u=A129283(n)); (u/gcd(u,sigma(n))); };

%Y Cf. A000203, A003415, A129283, A211991, A343226, A343227.

%K nonn

%O 1,4

%A _Antti Karttunen_, Jun 07 2021