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%I #16 Mar 27 2020 19:49:55
%S 1,1,3,7,17,21,49,69,105,103,217,173,375,347,435,509,863,601,1243,983,
%T 1271,1265,2217,1449,2575,2225,2935,2573,4549,2241,5601,4609,5195,
%U 4997,6453,4531,9519,7099,8457,6897,13111,6621,15255,11053,11691,12397,20033,11471,20905,14563,19307,17663,28901,16285,26119
%N a(n) = Sum_{i=1..n, gcd(i,n)=1} i*phi(i) where phi is Euler's totient function A000010.
%H Seiichi Manyama, <a href="/A333291/b333291.txt">Table of n, a(n) for n = 1..10000</a>
%p a:= n-> add(`if`(igcd(i, n)=1, i*numtheory[phi](i), 0), i=1..n):
%p seq(a(n), n=1..55); # _Alois P. Heinz_, Mar 22 2020
%o (PARI) a(n) = sum(i=1, n, if (gcd(n, i) == 1, i*eulerphi(i))); \\ _Michel Marcus_, Mar 23 2020
%Y Suggested by A023896 and A319087.
%Y Cf. A000010, A011755.
%K nonn,look
%O 1,3
%A _N. J. A. Sloane_, Mar 22 2020
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