A354097 a(n) = 1 if n-phi(n) is a multiple of 4, otherwise 0.

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

Offset

1

Links

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

Index entries for characteristic functions

Formula

a(n) = 1 iff A010873(A051953(n)) == 0.

Mathematica

a[n_] := If[Divisible[n - EulerPhi[n], 4] , 1, 0]; Array[a, 100] (* Amiram Eldar, May 17 2022 *)

Prog

(PARI) A354097(n) = (0==((n-eulerphi(n))%4));

Crossrefs

Characteristic function of A354098.

Cf. A000010, A010873, A051953.

Cf. also A354037.

Sequence in context: A353348 A359826 A353350 * A354927 A173861 A359464

Adjacent sequences: A354094 A354095 A354096 * A354098 A354099 A354100

Keyword

nonn

Author

Antti Karttunen, May 17 2022

Status

approved