A325321 a(n) = 1 if cototient of n is a square, 0 otherwise.

1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0

Offset

1

Comments

Characteristic function of A063752.

Links

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

Index entries for characteristic functions

Formula

a(n) = A010052(A051953(n)).

Mathematica

Array[Boole[IntegerQ@ Sqrt[# - EulerPhi@ #]] &, 105] (* Michael De Vlieger, Apr 21 2019 *)

Prog

(PARI) A325321(n) = issquare(n-eulerphi(n));

Crossrefs

Cf. A000010, A010052, A051953, A063752.

Sequence in context: A230901 A285671 A267773 * A255887 A359473 A181183

Adjacent sequences: A325318 A325319 A325320 * A325322 A325323 A325324

Keyword

nonn

Author

Antti Karttunen, Apr 21 2019

Status

approved