A362628 - OEIS

%I #6 Apr 28 2023 17:37:42

%S 1,3,1,7,1,12,1,15,1,3,1,28,1,3,1,31,1,39,1,22,1,3,1,60,1,3,1,7,1,12,

%T 1,63,1,3,1,91,1,3,1,50,1,33,1,7,1,3,1,124,1,3,1,7,1,120,1,15,1,3,1,

%U 43,1,3,1,127,1,12,1,7,1,3,1,195,1,3,1,7,1,12,1,106,1,3,1,140

%N a(n) = Sum_{d|n, phi(d)|n} d.

%t a[n_] := DivisorSum[n, # &, Divisible[n, EulerPhi[#]] &]; Array[a, 100]

%o (PARI) a(n) = sumdiv(n, d, if (!(n % eulerphi(d)), d)); \\ _Michel Marcus_, Apr 28 2023

%Y Cf. A000010 (phi), A069932, A362470.

%K nonn,easy

%O 1,2

%A _Wesley Ivan Hurt_, Apr 28 2023