A323169 Greatest common divisor of the set of solutions to phi(x) = n, or 0 if n is not a totient.

1, 1, 0, 1, 0, 1, 0, 1, 0, 11, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 23, 0, 1, 0, 0, 0, 29, 0, 31, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 23, 0, 47, 0, 1, 0, 0, 0, 53, 0, 81, 0, 29, 0, 59, 0, 1, 0, 0, 0, 1, 0, 67, 0, 0, 0, 71, 0, 1, 0, 0, 0, 0, 0, 79, 0, 1, 0, 83, 0, 1, 0, 0, 0, 1, 0, 0, 0, 47, 0, 0, 0, 1, 0, 0, 0, 1, 0, 103, 0, 53, 0

Offset

1,10

Links

Antti Karttunen, Table of n, a(n) for n = 1..16384

Max Alekseyev, PARI scripts for various problems

Formula

a(n) = 0 iff A014197(n) == 0.

Prog

(PARI) A323169(n) = gcd(invphi(n)); \\ With invphi from Max Alekseyev's PARI-script collection

Crossrefs

Cf. A000010, A014197, A303745 (positions of terms larger than one), A323514 (their characteristic function).

Sequence in context: A377778 A179920 A216726 * A143197 A138066 A173189

Adjacent sequences: A323166 A323167 A323168 * A323170 A323171 A323172

Keyword

nonn

Author

Antti Karttunen, Jan 18 2019

Status

approved