A181183 a(n) = sigma(tau(n)) (mod 2).

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

Offset

1,1

Links

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

Index entries for characteristic functions

Index entries for sequences computed from exponents in factorization of n

Formula

a(n) = A000035(A062069(n)). - Antti Karttunen, Nov 18 2017

Maple

A181183:= n-> (numtheory[sigma](numtheory[tau](n)) mod 2):
seq (A181183(n), n=1..105);

Mathematica

Array[Mod[DivisorSigma[1, DivisorSigma[0, #]], 2] &, 105] (* Michael De Vlieger, Nov 18 2017 *)

Prog

(PARI) A181183(n) = (sigma(numdiv(n))%2); \\ Antti Karttunen, Nov 18 2017

Crossrefs

Cf. A000035, A062069.

Sequence in context: A325321 A255887 A359473 * A295316 A014677 A307425

Adjacent sequences: A181180 A181181 A181182 * A181184 A181185 A181186

Keyword

nonn

Author

Jani Melik, Jan 26 2011

Status

approved