A127254 (0,1) sequence whose zero positions are indexed by twice the odious numbers given by A091855.

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

Offset

0,1

Comments

0's appear at positions indexed by 2*A091855(n).

Links

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

Index entries for characteristic functions.

Mathematica

a[n_] := If[EvenQ[n] && EvenQ[IntegerExponent[n/2, 2]] && OddQ[DigitCount[n/2, 2, 1]], 0, 1]; Array[a, 100, 0] (* Amiram Eldar, Aug 06 2023 *)

Prog

(PARI) A127254(n) = if(n%2, 1, !(hammingweight(n)%2 && !(valuation(n/2, 2)%2))); \\ After PARI-code in A091855. - Antti Karttunen, Nov 02 2018

Crossrefs

Row sums of A127253.

Cf. A000069, A091855.

Sequence in context: A070178 A364250 A289748 * A188395 A266678 A267936

Adjacent sequences: A127251 A127252 A127253 * A127255 A127256 A127257

Keyword

nonn,base

Author

Paul Barry, Jan 10 2007

Extensions

More terms from Antti Karttunen, Nov 02 2018

Status

approved