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%I #20 Feb 22 2020 08:32:32
%S 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,
%T 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,
%U 0,0,1,1,0,0,0,1,1,1,0,0,1,0,1,1,0,0,1,1,1,1
%N Write the odd numbers 2n - 1 in base 2 and juxtapose these binary expansions; read the result bit-by-bit.
%e 1 in binary is 1.
%e 3 in binary is 11.
%e 5 in binary is 101.
%e 7 in binary is 111.
%e 9 in binary is 1001.
%e 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.
%t Flatten[Table[IntegerDigits[2n - 1, 2], {n, 50}]] (* _Harvey P. Dale_, Aug 06 2013 *)
%o (Scala) (1 to 31 by 2).map(Integer.toString(_, 2)).mkString.split("").map(Integer.parseInt(_)).toList // _Alonso del Arte_, Feb 10 2020
%Y Cf. A099821 (odd positive integers in base 2).
%K nonn,base,easy
%O 1,1
%A _Clark Kimberling_