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A228495 Characteristic function of the odd odious numbers (A092246). 5
0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

The following sequences all appear to have the same parity: A003071, A029886, A061297, A092524, A093431, A102393, A104258, A122248, A128975. - Jeremy Gardiner, Dec 28 2008.

a(n+1) is the characteristic function of the even evil numbers (A125592). - Jeremy Gardiner, Feb 06 2015

LINKS

Antti Karttunen, Table of n, a(n) for n = 0..65537

Tanya Khovanova, There are no coincidences, arXiv preprint 1410.2193, 2014

Index entries for characteristic functions

Index entries for sequences related to binary expansion of n

FORMULA

a(2n) = 0, a(2n+1) = A092436(n).

a(n) = A000035(n) * A010060(n). - Antti Karttunen, Jan 12 2019

PROG

(PARI) a(n)=if(n%2==0, 0, subst(Pol(binary((n-1)/2)), x, 1)%2==0)

(PARI) A228495(n) = ((n%2)&&(hammingweight(n)%2)); \\ Antti Karttunen, Jan 12 2019

CROSSREFS

Cf. A000035, A010060, A092246, A254379.

Sequence in context: A162518 A330306 A300477 * A284683 A288673 A030213

Adjacent sequences:  A228492 A228493 A228494 * A228496 A228497 A228498

KEYWORD

nonn

AUTHOR

Ralf Stephan, Aug 23 2013

STATUS

approved

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Last modified March 7 19:49 EST 2021. Contains 341931 sequences. (Running on oeis4.)