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A138168 Numbers containing their length in binary representation. 3
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 (list; graph; refs; listen; history; text; internal format)
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

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Last modified May 11 13:21 EDT 2021. Contains 343791 sequences. (Running on oeis4.)