A323514 - OEIS

%I #7 Jan 18 2019 20:55:04

%S 0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,1,0,1,0,0,0,0,

%T 0,0,0,0,0,0,0,0,0,1,0,1,0,0,0,0,0,1,0,1,0,1,0,1,0,0,0,0,0,0,0,1,0,0,

%U 0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,1,0,1,0,1,0,0,0,1,0,0,0,0,0,1,0,0,0,0

%N a(n) = 1 if the greatest common divisor of the set of solutions to phi(x) = n is larger than one, otherwise 0.

%C Characteristic function of A303745.

%H Antti Karttunen, <a href="/A323514/b323514.txt">Table of n, a(n) for n = 1..65537</a>

%H Max Alekseyev, <a href="http://home.gwu.edu/~maxal/gpscripts/">PARI scripts for various problems</a>

%H <a href="/index/Ch#char_fns">Index entries for characteristic functions</a>

%F a(n) = [A323169(n) > 1], where [ ] is the Iverson bracket.

%o (PARI) A323514(n) = (gcd(invphi(n))>1); \\ With invphi from _Max Alekseyev_'s PARI-script collection

%Y Cf. A000010, A014197, A303745, A323169.

%K nonn

%O 1

%A _Antti Karttunen_, Jan 18 2019