%I #7 Jun 28 2024 21:10:58
%S 1,1,0,0,0,0,0,0,1,1,1,0,0,0,1,0,0,0,1,0,0,0,1,0,0,0,0,1,0,0,0,0,0,0,
%T 0,0,1,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,1,0,1,0,0,0,1,0,0,0,1,1,1,1,0,0,
%U 1,0,0,0,1,0,0,0,1,0,0,0,1,1,0,0,0,1,0,0,0,0,1,1,1,0,0,1,0,0,0,1,1,0,0,0,0,0,1,0,1,0,0,0,1,0,0,1,0,1,1,1,0,0,0,0,0,1
%N a(n) = 1 if A328845(n) is a multiple of 3, otherwise 0, where A328845 is the first Fibonacci-based variant of the arithmetic derivative.
%H Antti Karttunen, <a href="/A374121/b374121.txt">Table of n, a(n) for n = 0..100000</a>
%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
%F a(n) = A079978(A328845(n)).
%o (PARI)
%o A328845(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]*fibonacci(f[i,1])/f[i, 1]));
%o A374121(n) = !(A328845(n)%3);
%Y Characteristic function of A374122.
%Y Cf. A079978, A328845.
%Y Cf. also A374045, A374051.
%K nonn
%O 0
%A _Antti Karttunen_, Jun 28 2024
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