A118268 a(0)= A118269(0) = 1. Place A118269(n) written in binary to end of sequence A118268 (with each binary digit entered separately and where '0' is appended to sequence if A118269(n) = 0). A118269(n) is number of times n written in binary occurs among the earlier terms (before A118269(n) in binary is added) of this sequence concatenated.

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

Offset

0,1

Links

Michael De Vlieger, Table of n, a(n) for n = 0..10000

Example

21 in binary is 10101. This sequence up to just before the binary A118269(21) is appended is (after concatenation) 110101100011110101001. 10101 occurs twice in this concatenated string. So A118269(21) is 2 and {1,0} (representing a binary 2) is appended to the end of this sequence.

Mathematica

Fold[#1~Join~IntegerDigits[SequenceCount[#1, IntegerDigits[#2, 2]], 2] &, {1}, Range@ 91] (* Michael De Vlieger, Sep 30 2017 *)

Crossrefs

Cf. A118269.

Sequence in context: A279733 A176723 A189126 * A143220 A189163 A189129

Adjacent sequences: A118265 A118266 A118267 * A118269 A118270 A118271

Keyword

easy,nonn,base

Author

Leroy Quet, Apr 20 2006

Extensions

More terms from Franklin T. Adams-Watters, May 14 2010

Status

approved