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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
OFFSET
1,2
LINKS
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
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Mar 03 2008
STATUS
approved