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%I #5 Jan 27 2017 13:15:18
%S 0,1,3,1,3,7,6,2,6,14,15,7,5,13,12,4,12,28,29,13,15,31,30,14,10,26,27,
%T 11,9,25,24,8,24,56,57,25,27,59,58,26,30,62,63,31,29,61,60,28,20,52,
%U 53,21,23,55,54,22,18,50,51,19,17,49,48,16,48,112,113,49,51,115,114,50,54,118
%N Write n in binary reflected Gray code, rotate one binary place to the right and convert the code back to decimal.
%C a(n) = A003188(n), iff the Elias delta code for n contains all 1's without any zeros (see the example section).
%H Indranil Ghosh, <a href="/A281553/b281553.txt">Table of n, a(n) for n = 0..10000</a>
%e For n = 5, the binary reflected Gray code for n is '111'. Rotating one binary place to the right , '111' gives back '111' again. 111_2 = 7_10. So, a(5) = 7. (For n = 5, A003188(n) = 7).
%e For n = 15, the binary reflected Gray code for n is '1000'. Rotating one binary place to the right, '1000' gives '0100'. 100_2 = 4_10. So, a(15) = 4.
%o (Python)
%o def rotation(n):
%o ....x=bin(n^(n/2))[2:]
%o ....return int(x[-1]+x[:-1],2)
%Y Cf. A003188, A014550, A038572.
%K nonn,base
%O 0,3
%A _Indranil Ghosh_, Jan 24 2017
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