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%I #10 Dec 05 2017 21:20:18
%S 0,0,2,2,6,2,8,6,8,6,12,6,24,8,14,14,30,8,26,14,24,12,24,14,36,24,26,
%T 24,48,14,48,30,36,30,56,24,78,26,56,30,84,24,64,36,56,24,48,30,64,36,
%U 62,56,84,26,84,56,78,48,60,30,144,48,78,62,120,36,96
%N Sum of even divisors of phi(n).
%H Antti Karttunen, <a href="/A193388/b193388.txt">Table of n, a(n) for n = 1..16384</a>
%F a(n) = A146076(A000010(n)) = A062402(n) - A193454(n). - _Antti Karttunen_, Dec 05 2017
%e a(13) = 24 because phi(13) = 12 and the sum of the 4 even divisors { 2, 4, 6, 12} is 24.
%t Table[Total[Select[Divisors[EulerPhi[n]], EvenQ[ # ]&]], {n, 58}]
%o (PARI) A193388(n) = { my(s=eulerphi(n)); sumdiv(s,d,(!(d%2))*d); }; \\ _Antti Karttunen_, Dec 05 2017
%Y Cf. A000010, A062402, A146076, A193454.
%Y Cf. also A193322, A193386.
%K nonn
%O 1,3
%A _Michel Lagneau_, Jul 25 2011
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