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%I #12 Jul 13 2013 12:03:45
%S 1,1,5,9,17,25,37,41,41,41,45,49,73,81,109,113,113,113,117,121,129,
%T 169,213,217,217,217,221,225,281,289,349,353,353,353,357,361,369,377,
%U 389,457,521,585,653,721,809,817,845,913,977,1041,1109,1177,1249
%N a(0)=1, a(n) = (a(n-1) XOR n) + n.
%C a(n)>=n.
%H Reinhard Zumkeller, <a href="/A182388/b182388.txt">Table of n, a(n) for n = 0..10000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/XOR.html">XOR</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Binary_and#XOR">Bitwise operation XOR</a>
%F a(0)=1, a(n)=(a(n-1) XOR n) + n, where XOR is the bitwise exclusive-OR operator.
%e a(5) = (a(4) XOR 5) + 5 = (17 XOR 5) + 5 = 20+5 = 25
%o (Python)
%o a=1
%o for i in range(1,55):
%o . print a,
%o . a ^= i
%o . a += i
%o (Haskell)
%o import Data.Bits (xor)
%o a182388 n = a182388_list !! n
%o a182388_list = f 0 1 where
%o f x y = y' : f (x + 1) y' :: [Integer] where y' = (x `xor` y) + x
%o -- _Reinhard Zumkeller_, Apr 29 2012
%Y Cf. A182243, A182248.
%K nonn,base
%O 0,3
%A _Alex Ratushnyak_, Apr 27 2012
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