This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A179857 Smallest number greater than n having in binary representation exactly twice the number of ones as n has in binary representation. 4

%I

%S 3,3,15,5,15,15,63,9,15,15,63,15,63,63,255,17,23,23,63,23,63,63,255,

%T 27,63,63,255,63,255,255,1023,33,39,39,63,39,63,63,255,43,63,63,255,

%U 63,255,255,1023,51,63,63,255,63,255,255,1023,63,255,255,1023,255,1023,1023

%N Smallest number greater than n having in binary representation exactly twice the number of ones as n has in binary representation.

%C a(n) = Min{m: m > n and A000120(m) = 2*A000120(n)};

%C a(n) is odd;

%C n < a(n) < A000290(A062383(n));

%C a(A000079(n)) = A000051(n);

%C A024036 and A000225 give record values and where they occur.

%H R. Zumkeller, <a href="/A179857/b179857.txt">Table of n, a(n) for n = 1..1000</a>

%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>

%t br2[n_]:=Module[{k=If[EvenQ[n],n+1,n+2],t=2*DigitCount[n,2,1]},While[ DigitCount[ k,2,1]!=t,k=k+2];k]; Array[br2,70] (* _Harvey P. Dale_, Sep 20 2016 *)

%Y Cf. A086799.

%K base,nonn

%O 1,1

%A _Reinhard Zumkeller_, Jul 31 2010

%E Definition clarified by _Harvey P. Dale_, Sep 20 2016

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified July 17 18:47 EDT 2019. Contains 325109 sequences. (Running on oeis4.)