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A030317
Write the odd numbers 2n - 1 in base 2 and juxtapose these binary expansions; read the result bit-by-bit.
6
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
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
KEYWORD
nonn,base,easy
STATUS
approved