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%I #8 Jun 08 2021 00:00:06
%S 1,3,4,7,6,14,8,17,19,32,12,48,14,86,122,57,18,137,20,328,800,1058,24,
%T 250,651,4136,838,4252,30,1804,32,625,59204,65588,18062,4557,38,
%U 262202,531650,5394,42,51790,44,1049788,29018,4194374,48,8906,117699,1059277,43047062
%N a(n) = Sum_{d|n} d^phi(n/d).
%C If p is prime, a(p) = Sum_{d|p} d^phi(p/d) = 1^(p-1) + p^1 = p + 1.
%e a(6) = Sum_{d|6} d^phi(6/d) = 1^phi(6) + 2^phi(3) + 3^phi(2) + 6^phi(1) = 14.
%t Table[Sum[k^EulerPhi[n/k^(1 - Ceiling[n/k] + Floor[n/k])] (1 - Ceiling[n/k] + Floor[n/k]), {k, n}], {n, 80}]
%o (PARI) a(n) = sumdiv(n, d, d^eulerphi(n/d)); \\ _Michel Marcus_, May 21 2021
%Y Cf. A000010, A018804, A174476.
%K nonn
%O 1,2
%A _Wesley Ivan Hurt_, May 20 2021
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