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A324103 a(1) = 0; for n > 1, a(n) = A083254(A156552(n)).

%I A324103 #7 Feb 19 2019 00:09:38
%S A324103 0,1,0,1,0,3,0,5,-2,3,0,9,0,15,-2,1,0,11,0,17,-6,7,0,21,-4,31,-2,13,0,
%T A324103 3,0,29,-2,39,-4,9,0,255,-26,9,0,35,0,65,-2,135,0,45,-8,15,-34,129,0,
%U A324103 27,-12,69,-90,575,0,41,0,679,-2,9,-4,19,0,173,-2,39,0,25,0,3583,-2,301,-8,83,0,77,-14,2727,0,5,-52,8703,-378,9,0,3
%N A324103 a(1) = 0; for n > 1, a(n) = A083254(A156552(n)).
%H A324103 Antti Karttunen, <a href="/A324103/b324103.txt">Table of n, a(n) for n = 1..4473</a>
%F A324103 a(1) = 0; for n > 1, a(n) = A083254(A156552(n)).
%F A324103 a(n) = 2*A324104(n) - A156552(n).
%o A324103 (PARI)
%o A324103 A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
%o A324103 A156552(n) = if(1==n, 0, if(!(n%2), 1+(2*A156552(n/2)), 2*A156552(A064989(n))));
%o A324103 A083254(n) = (2*eulerphi(n)-n);
%o A324103 A324103(n) = if(1==n,0,A083254(A156552(n)));
%Y A324103 Cf. A000010, A083254, A156552, A323244, A324104, A324105.
%Y A324103 Cf. also A324052, A324182.
%K A324103 sign
%O A324103 1,6
%A A324103 _Antti Karttunen_, Feb 18 2019