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A359792 a(n) = (-1)^A003415(n), where A003415 is the arithmetic derivative of n. 3

%I #7 Jan 14 2023 18:36:51

%S 1,-1,-1,1,-1,-1,-1,1,1,-1,-1,1,-1,-1,1,1,-1,-1,-1,1,1,-1,-1,1,1,-1,

%T -1,1,-1,-1,-1,1,1,-1,1,1,-1,-1,1,1,-1,-1,-1,1,-1,-1,-1,1,1,-1,1,1,-1,

%U -1,1,1,1,-1,-1,1,-1,-1,-1,1,1,-1,-1,1,1,-1,-1,1,-1,-1,-1,1,1,-1,-1,1,1,-1,-1,1,1,-1,1,1,-1,-1,1,1,1,-1,1,1,-1,-1,-1,1,-1,-1,-1,1,-1

%N a(n) = (-1)^A003415(n), where A003415 is the arithmetic derivative of n.

%C Not multiplicative.

%H Antti Karttunen, <a href="/A359792/b359792.txt">Table of n, a(n) for n = 1..20000</a>

%F a(n) = (-1)^A165560(n).

%F a(n) = A358680(n) - A165560(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 A359792(n) = ((-1)^A003415(n));

%Y Cf. A003415, A165560, A358680, A359793 (Dirichlet inverse).

%K sign

%O 1

%A _Antti Karttunen_, Jan 14 2023

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Last modified June 6 15:18 EDT 2024. Contains 373131 sequences. (Running on oeis4.)