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%I A360109 #9 Feb 01 2023 16:06:29
%S A360109 0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
%T A360109 0,1,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,
%U A360109 0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,1
%N A360109 a(n) = 1 if n is not multiple of 4, but its arithmetic derivative is, otherwise 0.
%H A360109 Antti Karttunen, <a href="/A360109/b360109.txt">Table of n, a(n) for n = 0..100000</a>
%H A360109 <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
%F A360109 a(n) = A166486(n) * A353494(n).
%o A360109 (PARI)
%o A360109 A003415(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]/f[i, 1]));
%o A360109 A360109(n) = ((n%4)&&(0==(A003415(n)%4)));
%Y A360109 Characteristic function of A360110.
%Y A360109 Cf. A003415, A166486, A353494, A359828.
%Y A360109 After n=1 differs from A327932 for the first time at n=158, where a(158) = 0, while A327932(158) = 1.
%K A360109 nonn
%O A360109 0
%A A360109 _Antti Karttunen_, Jan 31 2023

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