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%I #25 Jun 30 2022 18:00:55
%S 0,1,2,3,6,5,6,7,14,13,14,11,14,13,14,15,30,29,30,27,30,29,30,23,30,
%T 29,30,27,30,29,30,31,62,61,62,59,62,61,62,55,62,61,62,59,62,61,62,47,
%U 62,61,62,59,62,61,62,55,62,61,62,59,62,61,62,63,126,125,126,123,126,125
%N a(n) = OR{k XOR (n-k): 0<=k<=n}.
%H Reinhard Zumkeller, <a href="/A142151/b142151.txt">Table of n, a(n) for n = 0..10000</a>
%H Reinhard Zumkeller, <a href="/A142149/a142149.txt">Logical Convolutions</a>
%F a(2*n) = 2*(A062383(n)-1);
%F A023416(a(n)) <= 1.
%p A142151 := n -> n + Bits:-Nor(n, n+1):
%p seq(A142151(n), n=0..69); # _Peter Luschny_, Sep 26 2019
%o (Haskell)
%o import Data.Bits (xor, (.|.))
%o a142151 :: Integer -> Integer
%o a142151 = foldl (.|.) 0 . zipWith xor [0..] . reverse . enumFromTo 1
%o -- _Reinhard Zumkeller_, Mar 31 2015
%o (Julia)
%o using IntegerSequences
%o A142151List(len) = [Bits("CIMP", n, n+1) for n in 0:len]
%o println(A142151List(69)) # _Peter Luschny_, Sep 25 2021
%o (Python)
%o from functools import reduce
%o from operator import or_
%o def A142151(n): return 0 if n == 0 else reduce(or_,(k^n-k for k in range(n+1))) if n % 2 else (1 << n.bit_length()-1)-1 <<1 # _Chai Wah Wu_, Jun 30 2022
%Y Cf. A003817, A000004, A142149, A086099, A142150, A001477, A089633.
%K nonn,hear,look
%O 0,3
%A _Reinhard Zumkeller_, Jul 15 2008
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