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A319340 Sum of Euler totient function and its Dirichlet inverse: a(n) = A000010(n) + A023900(n).

%I A319340 #7 Sep 17 2018 22:26:05
%S A319340 2,0,0,1,0,4,0,3,4,8,0,6,0,12,16,7,0,8,0,12,24,20,0,10,16,24,16,18,0,
%T A319340 0,0,15,40,32,48,14,0,36,48,20,0,0,0,30,32,44,0,18,36,24,64,36,0,20,
%U A319340 80,30,72,56,0,8,0,60,48,31,96,0,0,48,88,0,0,26,0,72,48,54,120,0,0,36,52,80,0,12,128,84,112,50,0,16
%N A319340 Sum of Euler totient function and its Dirichlet inverse: a(n) = A000010(n) + A023900(n).
%H A319340 Antti Karttunen, <a href="/A319340/b319340.txt">Table of n, a(n) for n = 1..65537</a>
%F A319340 a(n) = A000010(n) + A023900(n).
%F A319340 a(n) = A318833(n) - A051953(n).
%o A319340 (PARI)
%o A319340 A023900(n) = factorback(apply(p -> 1-p, factor(n)[, 1]));
%o A319340 A319340(n) = (eulerphi(n)+A023900(n));
%Y A319340 Cf. A000010, A023900, A051953, A318833, A319341.
%K A319340 nonn
%O A319340 1,1
%A A319340 _Antti Karttunen_, Sep 17 2018