A340195 - OEIS

%I #7 Jan 02 2021 18:03:04

%S 1,2,3,3,5,5,7,4,5,7,11,7,13,9,9,5,17,8,19,9,13,13,23,9,9,15,7,13,29,

%T 13,31,6,17,19,13,11,37,21,17,11,41,17,43,15,15,25,47,11,13,12,21,19,

%U 53,11,17,15,25,31,59,17,61,33,17,7,33,25,67,21,29,19,71,14,73,39,15,25,21,21,79,13,9,43,83,23,25,45,33

%N a(n) = Sum_{divisors d of n} A049559(d), where A049559(x) = gcd(phi(x), x-1).

%H Antti Karttunen, <a href="/A340195/b340195.txt">Table of n, a(n) for n = 1..16384</a>

%F a(n) = Sum_{d|n} A049559(d).

%F a(n) = n - A340196(n).

%o (PARI)

%o A049559(n) = gcd(eulerphi(n), n-1);

%o A340195(n) = sumdiv(n,d,A049559(d));

%Y Inverse Möbius transform of A049559.

%Y Cf. A000010, A340196.

%Y Cf. also A340192.

%K nonn

%O 1,2

%A _Antti Karttunen_, Jan 02 2021