A165265 Concatenate the number of 1's and number of 0's in the binary expansion of n.

1, 10, 11, 20, 12, 21, 21, 30, 13, 22, 22, 31, 22, 31, 31, 40, 14, 23, 23, 32, 23, 32, 32, 41, 23, 32, 32, 41, 32, 41, 41, 50, 15, 24, 24, 33, 24, 33, 33, 42, 24, 33, 33, 42, 33, 42, 42, 51, 24, 33, 33, 42, 33, 42, 42, 51, 33, 42, 42, 51, 42, 51, 51, 60, 16, 25, 25, 34, 25, 34

Offset

0,2

Links

Michael De Vlieger, Table of n, a(n) for n = 0..4096

Example

a(7) = 30 because "111" has three 0's and zero 1's.
a(8) = 13 because "1000" has one 1 and three 0's.
From Michael De Vlieger, Sep 23 2017: (Start)
a(1023) = 100 because "1111111111" has no 0's and ten 1's.
a(2048) = 111 because "100000000000" has eleven 0's and one 1. (End)

Mathematica

f[n_]:=Module[{idn2=IntegerDigits[n, 2]}, FromDigits[Join[{Count[idn2, 1], Count[idn2, 0]}]]]
f/@Range[0, 80]  (* Harvey P. Dale, Feb 14 2011 *)
Table[FromDigits@ Flatten@ Map[IntegerDigits, DigitCount[n, 2]], {n, 0, 73}] (* Michael De Vlieger, Sep 23 2017 *)

Crossrefs

Sequence in context: A214790 A191221 A216996 * A329818 A329447 A352339

Adjacent sequences: A165262 A165263 A165264 * A165266 A165267 A165268

Keyword

base,easy,nonn,less

Author

Gil Broussard, Sep 12 2009

Extensions

Edited by Charles R Greathouse IV, Mar 23 2010

Status

approved