OFFSET
1,1
COMMENTS
Clarification: A binary number consists of "runs" completely of 1's alternating with runs completely of 0's. No two or more runs all of the same digit are adjacent.
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
100 is a term since its binary expansion "1100100" has two groups of zeros that are of the same length. - Michael De Vlieger, Nov 04 2017
MATHEMATICA
brQ[n_]:=Module[{rz=Select[Split[IntegerDigits[n, 2]], MemberQ[#, 0]&]}, Length[ rz]>1 && Length[Union[Length/@rz]]==1]; Select[Range[250], brQ] (* Harvey P. Dale, Mar 23 2015 *)
Select[Range[2^8], And[Length@ # > 1, Length@ Union@ # == 1] &@ Map[Length, Select[Split@ IntegerDigits[#, 2], First@ # == 0 &]] &] (* Michael De Vlieger, Nov 04 2017 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Leroy Quet, Aug 23 2009
EXTENSIONS
More terms from Sean A. Irvine, Sep 28 2009
STATUS
approved