A066970 - OEIS

%I #19 Jun 06 2022 05:48:06

%S 1,4,20,58,178,248,880,965,2289,2664,4096,3233,7254,15447,30658,35869,

%T 49485,102248,116225,272130,247872,322891,407484,521003,444794,929334,

%U 1022620,1653250,1792704,1859231,2070655,2906985,3965654,6952192,10631022,11049130

%N Integers of the form Sum_{i=1..m} phi(i)/gcd(m,i).

%H Amiram Eldar, <a href="/A066970/b066970.txt">Table of n, a(n) for n = 1..100</a>

%t Select[Table[Sum[EulerPhi[i]/GCD[m,i],{i,m}],{m,2000}],IntegerQ] (* _Harvey P. Dale_, Jun 05 2012 *)

%o (PARI) lista(nn) = {for (n = 1, nn, if (type(v = sum(i=1, n, eulerphi(i)/gcd(n,i))) == "t_INT", print1(v, ", ")););} \\ _Michel Marcus_, Nov 20 2013

%Y Cf. A066969.

%K nonn

%O 1,2

%A _Benoit Cloitre_, Jan 26 2002

%E More terms from _Michel Marcus_, Nov 20 2013