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A142149 a(n) = XOR{k OR (n-k): 0<=k<=n}. 6
0, 1, 3, 3, 6, 5, 5, 7, 12, 9, 15, 11, 10, 13, 9, 15, 24, 17, 27, 19, 30, 21, 29, 23, 20, 25, 23, 27, 18, 29, 17, 31, 48, 33, 51, 35, 54, 37, 53, 39, 60, 41, 63, 43, 58, 45, 57, 47, 40, 49, 43, 51, 46, 53, 45, 55, 36, 57, 39, 59, 34, 61, 33, 63, 96, 65, 99, 67, 102, 69, 101, 71 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

a(n) = XOR{k AND (n-k): 0<=k<=n} = XOR{k AND (n-k): 0<=k<=n}.

LINKS

R. Zumkeller, Table of n, a(n) for n = 0..10000

R. Zumkeller, Logical Convolutions

FORMULA

a(2*n)=A048724(n) and a(2*n+1)=A005408(n).

PROG

(Haskell)

import Data.Bits (xor, (.|.))

a142149 :: Integer -> Integer

a142149 = foldl xor 0 . zipWith (.|.) [0..] . reverse . enumFromTo 1

-- Reinhard Zumkeller, Mar 31 2015

CROSSREFS

Cf. A003817, A000004, A086099, A142150, A142151, A001477.

Sequence in context: A050346 A319619 A309001 * A132119 A180681 A286102

Adjacent sequences:  A142146 A142147 A142148 * A142150 A142151 A142152

KEYWORD

nonn,hear,look

AUTHOR

Reinhard Zumkeller, Jul 15 2008

STATUS

approved

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Last modified April 17 04:36 EDT 2021. Contains 343059 sequences. (Running on oeis4.)