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A102390
An odious count.
3
0, 1, 2, 0, 3, 0, 0, 4, 5, 0, 0, 6, 0, 7, 8, 0, 9, 0, 0, 10, 0, 11, 12, 0, 0, 13, 14, 0, 15, 0, 0, 16, 17, 0, 0, 18, 0, 19, 20, 0, 0, 21, 22, 0, 23, 0, 0, 24, 0, 25, 26, 0, 27, 0, 0, 28, 29, 0, 0, 30, 0, 31, 32, 0, 33, 0, 0, 34, 0, 35, 36, 0, 0, 37, 38, 0, 39, 0, 0, 40, 0, 41, 42, 0, 43, 0, 0, 44
OFFSET
0,3
COMMENTS
Counting numbers appear at positions indexed by the odious numbers A000069, 0 otherwise.
Equals row sums of triangle A143466 starting with offset 1. - Gary W. Adamson, Aug 17 2008
LINKS
FORMULA
a(n) = (1+floor(n/2))*(1-(-1)^A000120(n))/2.
a(n) = (1+floor(n/2))*(1-(-1)^A010060(n))/2.
A008619(n) = A102389(n) + a(n).
MATHEMATICA
a[n_] := (1 + Floor[n/2])*(1 - (-1)^DigitCount[n, 2, 1])/2; Array[a, 100, 0] (* Amiram Eldar, Jul 22 2023 *)
CROSSREFS
KEYWORD
easy,nonn,base
AUTHOR
Paul Barry, Jan 06 2005
STATUS
approved