A318934 - OEIS

%I #15 Oct 15 2022 16:42:20

%S 3,6,12,13,24,25,26,27,48,49,50,51,52,53,54,55,96,97,98,99,100,101,

%T 102,103,104,105,106,107,108,109,110,111,192,193,194,195,196,197,198,

%U 199,200,201,202,203,204,205,206,207,208,209,210,211,212,213,214,215,216,217,218,219,220,221,222,223

%N Numbers whose binary expansion begins with exactly two 1's.

%H Seiichi Manyama, <a href="/A318934/b318934.txt">Table of n, a(n) for n = 1..10000</a>

%e 3 11

%e 6 110

%e 12 1100

%e 13 1101

%e 24 11000

%e 25 11001

%e 26 11010

%e 27 11011

%e 48 110000

%e 49 110001

%e ...

%t Join[{3},Select[Range[4,250],Take[IntegerDigits[#,2],3]=={1,1,0}&]] (* _Harvey P. Dale_, Oct 15 2022 *)

%Y This is the union of {3} and A004758.

%Y Cf. A007088.

%K nonn,base,easy

%O 1,1

%A _N. J. A. Sloane_, Sep 13 2018