This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A269170 #26 Aug 26 2025 08:48:20
%S A269170 0,1,3,3,6,7,7,7,12,13,15,15,14,15,15,15,24,25,27,27,30,31,31,31,28,
%T A269170 29,31,31,30,31,31,31,48,49,51,51,54,55,55,55,60,61,63,63,62,63,63,63,
%U A269170 56,57,59,59,62,63,63,63,60,61,63,63,62,63,63,63,96,97,99,99,102,103,103,103,108,109,111,111,110,111
%N A269170 a(n) = n OR floor(n/2), where OR is bitwise-OR (A003986).
%C A269170 Fibbinary numbers (A003714) give all integers n >= 0 for which a(n) = A003188(n) and also for which a(n) = A032766(n).
%H A269170 Antti Karttunen, <a href="/A269170/b269170.txt">Table of n, a(n) for n = 0..8191</a>
%F A269170 a(n) = A003986(n,(n-A000035(n))/2).
%F A269170 Other identities and observations. For all n >= 0:
%F A269170 a(2n) = A163617(n).
%F A269170 A003188(n) <= a(n) <= A032766(n).
%t A269170 Table[BitOr[n, Quotient[n, 2]], {n, 0, 127}] (* _Paolo Xausa_, Aug 26 2025 *)
%o A269170 (Scheme)
%o A269170 (define (A269170 n) (A003986bi n (/ (- n (A000035 n)) 2))) ;; Here A003986bi implements dyadic bitwise-OR operation (see A003986).
%o A269170 (PARI) a(n) = bitor(n, n\2); \\ _Michel Marcus_, Feb 29 2016
%o A269170 (Python)
%o A269170 def A269170(n): return n| n>>1 # _Chai Wah Wu_, Jun 29 2022
%Y A269170 Cf. A000035, A003714, A003986.
%Y A269170 Cf. A163617 (even bisection).
%Y A269170 Cf. also A003188, A048735, A032766.
%K A269170 nonn,base,easy,look,changed
%O A269170 0,3
%A A269170 _Antti Karttunen_, Feb 22 2016