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%I #5 Feb 28 2021 20:29:38
%S 0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,
%T 1,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,1,0,
%U 0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1
%N a(n) = 1 if the arithmetic derivative (A003415) of n is a prime, otherwise 0.
%H Antti Karttunen, <a href="/A341995/b341995.txt">Table of n, a(n) for n = 0..65537</a>
%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>
%F a(n) = A010051(A003415(n)).
%F For all n > 0, a(n) <= A341994(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 A341995(n) = isprime(A003415(n));
%Y Characteristic function of A157037.
%Y Cf. A003415, A010051, A341994.
%K nonn
%O 0
%A _Antti Karttunen_, Feb 28 2021