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A181183 a(n) = sigma(tau(n)) (mod 2). 1
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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

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: A285668 A267813 A323000 * A005713 A188031 A305387

Adjacent sequences:  A181180 A181181 A181182 * A181184 A181185 A181186

KEYWORD

nonn

AUTHOR

Jani Melik, Jan 26 2011

STATUS

approved

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Last modified July 28 19:33 EDT 2021. Contains 346335 sequences. (Running on oeis4.)