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Those positive integers n that contain runs of 0's and 1's that are each a power of 2 in length when n is represented in binary.
0

%I #11 Oct 30 2019 15:30:17

%S 1,2,3,4,5,6,9,10,11,12,13,15,16,18,19,20,21,22,25,26,27,30,33,36,37,

%T 38,41,42,43,44,45,47,48,50,51,52,53,54,60,61,66,67,73,74,75,76,77,79,

%U 80,82,83,84,85,86,89,90,91,94,97,100,101,102,105,106,107,108,109,111,121

%N Those positive integers n that contain runs of 0's and 1's that are each a power of 2 in length when n is represented in binary.

%C Let the binary representation of n be thought of as a string of 0's and 1's. By a "run" of 0's or 1's, it is meant either a contiguous substring all of 0's bounded by 1's or the by the edge of the string, or a contiguous substring all of 1's bounded by 0's or the by the edge of the string.

%t Select[Range[150],And@@IntegerQ/@(Log[2,# ]&/@Length/@Split[IntegerDigits[ #,2]])&] (* _Ray Chandler_, May 19 2009 *)

%K base,nonn

%O 1,2

%A _Leroy Quet_, May 17 2009

%E Extended by _Ray Chandler_, May 19 2009