A127252 Sequence composed of 1 and -1 with the -1's occurring at odious indexed positions given by A091855.

1, -1, 1, 1, -1, 1, 1, -1, 1, 1, 1, -1, 1, -1, 1, 1, -1, 1, 1, -1, 1, -1, 1, 1, 1, -1, 1, 1, -1, 1, 1, -1, 1, 1, 1, -1, 1, -1, 1, 1, 1, -1, 1, 1, -1, 1, 1, -1, 1, -1, 1, 1, -1, 1, 1, -1, 1, 1, 1, -1, 1, -1, 1, 1, -1, 1, 1, -1, 1, -1, 1, 1, 1, -1, 1, 1, -1, 1, 1

Offset

0,1

Links

Table of n, a(n) for n=0..78.

Mathematica

a[n_] := If[EvenQ[IntegerExponent[n, 2]] && OddQ[DigitCount[n, 2, 1]], -1, 1]; Array[a, 100, 0] (* Amiram Eldar, Aug 04 2023 *)

Crossrefs

Row sums of A127251.

Partial sums are A127255.

Cf. A000069, A091855, A127245.

Sequence in context: A330034 A010555 A108784 * A244513 A376149 A020985

Adjacent sequences: A127249 A127250 A127251 * A127253 A127254 A127255

Keyword

sign,base

Author

Paul Barry, Jan 10 2007

Extensions

More terms from Amiram Eldar, Aug 04 2023

Status

approved