A323514 a(n) = 1 if the greatest common divisor of the set of solutions to phi(x) = n is larger than one, otherwise 0.

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, 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, 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

Offset

1

Comments

Characteristic function of A303745.

Links

Antti Karttunen, Table of n, a(n) for n = 1..65537

Max Alekseyev, PARI scripts for various problems

Index entries for characteristic functions

Formula

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

Prog

(PARI) A323514(n) = (gcd(invphi(n))>1); \\ With invphi from Max Alekseyev's PARI-script collection

Crossrefs

Cf. A000010, A014197, A303745, A323169.

Sequence in context: A025468 A373971 A025465 * A369660 A353495 A302047

Adjacent sequences: A323511 A323512 A323513 * A323515 A323516 A323517

Keyword

nonn

Author

Antti Karttunen, Jan 18 2019

Status

approved