A323402 a(n) = 1 if A023900(n) > 0 and A000010(A023900(n)) == A023900(A000010(n)), otherwise a(n) = 0. Here A000010 is Euler totient function phi, and A023900 is its Dirichlet inverse.

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

Offset

1

Comments

Characteristic function of A306146.

For all i, j: A323371(i) = A323371(j) => a(i) = a(j).

Links

Antti Karttunen, Table of n, a(n) for n = 1..100000

Index entries for characteristic functions

Prog

(PARI)
A023900(n) = sumdivmult(n, d, d*moebius(d)); \\ From A023900
A323402(n) = { my(k=A023900(n)); ((k>0)&&(eulerphi(k) == A023900(eulerphi(n)))); };

Crossrefs

Cf. A000010, A023900, A306146, A323371.

Sequence in context: A353675 A373137 A015868 * A240355 A358841 A015824

Adjacent sequences: A323399 A323400 A323401 * A323403 A323404 A323405

Keyword

nonn

Author

Antti Karttunen, Jan 18 2019

Status

approved