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 A306905 a(n) = A306898(n)/2. 0

%I

%S 1,4,6,16,20,48,70,160,270,560,1034,2160,4108,8344,16440,33088,65552,

%T 131688,262162,525440,1048740,2099240,4194326,8393184,16777300,

%U 33562672,67109418,134234464,268435484,536904960,1073741854,2147549824,4294969404

%N a(n) = A306898(n)/2.

%H Michael De Vlieger, <a href="/A306905/b306905.txt">Table of n, a(n) for n = 1..3322</a>

%t Table[DivisorSum[n, 2^#*EulerPhi[2 n/#] &]/2, {n, 33}] (* _Michael De Vlieger_, Dec 01 2019 *)

%Y Cf. A306898.

%K nonn,changed

%O 1,2

%A _Michael De Vlieger_ and _N. J. A. Sloane_, Mar 15 2019

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Last modified December 5 20:54 EST 2019. Contains 329779 sequences. (Running on oeis4.)