A138168 Numbers containing their length in binary representation.

1, 2, 6, 7, 8, 9, 12, 20, 21, 22, 23, 26, 27, 29, 38, 44, 45, 46, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 71, 78, 79, 87, 92, 93, 94, 95, 103, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130

Offset

1,2

Links

R. Zumkeller, Table of n, a(n) for n = 1..10000

Example

20 ->'10100', length = 5 ->'101', therefore 20 is a term;
200 ->'11001000', length = 8 ->'1000', therefore 200 is a term.

Mathematica

lbrQ[n_]:=Module[{idn2=IntegerDigits[n, 2]}, SequenceCount[idn2, IntegerDigits[ Length[ idn2], 2]]>0]; Select[Range[200], lbrQ] (* The program uses the SequenceCount function from Mathematica version 10 *) (* Harvey P. Dale, Oct 07 2015 *)

Crossrefs

Cf. A070939, A138166, A138167.

Sequence in context: A159843 A243652 A080780 * A047279 A162917 A250183

Adjacent sequences: A138165 A138166 A138167 * A138169 A138170 A138171

Keyword

nonn,base

Author

Reinhard Zumkeller, Mar 03 2008

Status

approved