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A127252
Sequence composed of 1 and -1 with the -1's occurring at odious indexed positions given by A091855.
2
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
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.
Sequence in context: A330034 A010555 A108784 * A244513 A376149 A020985
KEYWORD
sign,base
AUTHOR
Paul Barry, Jan 10 2007
EXTENSIONS
More terms from Amiram Eldar, Aug 04 2023
STATUS
approved