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A374047 Numbers k for which A328845(k) is odd, where A328845 is the first Fibonacci based variant of arithmetic derivative.

%I A374047 #14 Dec 16 2024 13:28:22
%S A374047 2,5,6,7,10,11,13,14,15,17,18,19,21,22,23,26,29,30,31,33,34,37,38,39,
%T A374047 41,42,43,45,46,47,50,51,53,54,57,58,59,61,62,63,66,67,69,70,71,73,74,
%U A374047 78,79,82,83,86,87,89,90,93,94,97,98,99,101,102,103,106,107,109,110,111,113,114,117,118,122,123,125,126,127
%N A374047 Numbers k for which A328845(k) is odd, where A328845 is the first Fibonacci based variant of arithmetic derivative.
%H A374047 Antti Karttunen, <a href="/A374047/b374047.txt">Table of n, a(n) for n = 1..12000</a>
%t A374047 A374047Q[k_] := If[k <= 1, False,OddQ[k*Total[MapApply[#2*Fibonacci[#]/# &, FactorInteger[k]]]]];
%t A374047 Select[Range[0, 200], A374047Q] (* _Paolo Xausa_, Dec 16 2024 *)
%o A374047 (PARI) isA374047(n) = !A374045(n);
%Y A374047 Cf. A000045, A328845, A374045, A374046 (complement).
%K A374047 nonn
%O A374047 1,1
%A A374047 _Antti Karttunen_, Jun 27 2024