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Arithmetic derivative of the odd part of n: a(n) = A003415(A000265(n)).
5

%I #8 Jan 27 2024 18:51:23

%S 0,0,1,0,1,1,1,0,6,1,1,1,1,1,8,0,1,6,1,1,10,1,1,1,10,1,27,1,1,8,1,0,

%T 14,1,12,6,1,1,16,1,1,10,1,1,39,1,1,1,14,10,20,1,1,27,16,1,22,1,1,8,1,

%U 1,51,0,18,14,1,1,26,12,1,6,1,1,55,1,18,16,1,1,108,1,1,10,22,1,32,1,1,39,20,1,34,1,24

%N Arithmetic derivative of the odd part of n: a(n) = A003415(A000265(n)).

%H Antti Karttunen, <a href="/A369465/b369465.txt">Table of n, a(n) for n = 1..16384</a>

%F a(n) = A003415(A000265(n)) = A349905(A064989(n)).

%o (PARI)

%o A000265(n) = (n>>valuation(n,2));

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

%o A369465(n) = A003415(A000265(n));

%Y Cf. A000265, A003415, A064989, A349905, A369466 (rgs-transform).

%Y Cf. also A369449.

%K nonn

%O 1,9

%A _Antti Karttunen_, Jan 27 2024