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%I #24 Jun 29 2022 17:40:52
%S 0,1,2,2,4,5,4,4,8,9,10,10,8,9,8,8,16,17,18,18,20,21,20,20,16,17,18,
%T 18,16,17,16,16,32,33,34,34,36,37,36,36,40,41,42,42,40,41,40,40,32,33,
%U 34,34,36,37,36,36,32,33,34,34,32,33,32,32,64,65,66,66,68,69,68,68,72,73,74,74,72,73,72,72,80,81,82,82,84,85,84,84,80,81,82,82,80,81
%N a(n) = n - A048735(n) = n - (n AND floor(n/2)).
%C In binary expansion of n, change those 1's to 0's that have an 1-bit next to them at their left (more significant) side. Only fibbinary numbers (A003714) occur as terms.
%H Antti Karttunen, <a href="/A292272/b292272.txt">Table of n, a(n) for n = 0..16383</a>
%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>
%F a(n) = n - A048735(n) = n - (n AND floor(n/2)) = n XOR (n AND floor(n/2)), where AND is bitwise-AND (A004198) and XOR is bitwise-XOR (A003987).
%F a(n) = n AND A003188(n).
%F a(n) = A292382(A005940(1+n)).
%F A059905(a(n)) = A292371(n).
%F For all n >= 0, A085357(a(n)) = 1.
%F a(n) = A213064(n) / 2. - _Kevin Ryde_, Jun 02 2020
%F a(n) = n AND NOT floor(n/2). - _Chai Wah Wu_, Jun 29 2022
%e From _Kevin Ryde_, Jun 02 2020: (Start)
%e n = 1831 = binary 11100100111
%e a(n) = 1060 = binary 10000100100 high 1 of each run
%e (End)
%t Table[n - BitAnd[n, Floor[n/2]], {n, 0, 93}] (* _Michael De Vlieger_, Sep 17 2017 *)
%o (PARI) a(n) = bitnegimply(n,n>>1); \\ _Kevin Ryde_, Jun 02 2020
%o (Python)
%o def A292272(n): return n&~(n>>1) # _Chai Wah Wu_, Jun 29 2022
%Y Cf. A003188, A003714, A003987, A004198, A005940, A048735, A085357, A292371, A292382.
%K nonn,base
%O 0,3
%A _Antti Karttunen_, Sep 16 2017
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