A030317 Write the odd numbers 2n - 1 in base 2 and juxtapose these binary expansions; read the result bit-by-bit.

1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 1, 1

Offset

1,1

Links

Table of n, a(n) for n=1..90.

Example

1 in binary is 1.
3 in binary is 11.
5 in binary is 101.
7 in binary is 111.
9 in binary is 1001.
Putting those together, we obtain 1111011111001. Then, splitting bit by bit, we get 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 0, 1, the beginning of this sequence.

Mathematica

Flatten[Table[IntegerDigits[2n - 1, 2], {n, 50}]] (* Harvey P. Dale, Aug 06 2013 *)

Prog

(Scala) (1 to 31 by 2).map(Integer.toString(_, 2)).mkString.split("").map(Integer.parseInt(_)).toList // Alonso del Arte, Feb 10 2020

Crossrefs

Cf. A099821 (odd positive integers in base 2).

Sequence in context: A187967 A106467 A106468 * A077009 A078556 A144093

Adjacent sequences: A030314 A030315 A030316 * A030318 A030319 A030320

Keyword

nonn,base,easy

Author

Clark Kimberling

Status

approved