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A161560 a(n) = floor(A000069(n)/2-1/2). 1
0, 0, 1, 3, 3, 5, 6, 6, 7, 9, 10, 10, 12, 12, 13, 15, 15, 17, 18, 18, 20, 20, 21, 23, 24, 24, 25, 27, 27, 29, 30, 30, 31, 33, 34, 34, 36, 36, 37, 39, 40, 40, 41, 43, 43, 45, 46, 46, 48, 48, 49, 51, 51, 53, 54, 54, 55, 57, 58, 58, 60, 60, 61, 63, 63, 65, 66, 66, 68, 68, 69, 71, 72 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

COMMENTS

Plays the role of an inverse function to A093505.

LINKS

Table of n, a(n) for n=1..73.

FORMULA

a(n) = A000069(n) - n.

EXAMPLE

a(5) = 3 because the fifth odious number = 8 and floor(8/2 - 1/2) = 3. Also 8 - 5 = 3.

PROG

(PARI) a(n)=n-1-hammingweight(n-1)%2 \\ Charles R Greathouse IV, Mar 29 2013

CROSSREFS

Cf. A000069.

Sequence in context: A131948 A134636 A088564 * A078796 A201929 A079789

Adjacent sequences:  A161557 A161558 A161559 * A161561 A161562 A161563

KEYWORD

nonn,easy

AUTHOR

Jaroslav Krizek, Jun 13 2009

STATUS

approved

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Last modified October 22 10:24 EDT 2019. Contains 328317 sequences. (Running on oeis4.)