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A118247 a(0)=0. Concatenate onto the end of the sequence (from left to right) the integer m_n converted into binary (with the most significant digit on the left), where m_n is the smallest integer > A118248(n-1) and whose binary representation does not occur anywhere earlier in the sequence (when the concatenated sequence is read from left to right). A118248(n) then equals m_n when written in decimal. 7
0, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Sequence can be regarded as an irregular number triangle containing the binary digits of A118248(n) in row n. - Michael De Vlieger, Aug 19 2017

LINKS

Michael De Vlieger, Table of n, a(n) for n = 0..11419 (Concatenation of A118248(0) through A118248(1000) inclusive).

EXAMPLE

The sequence begins 0,1,1,0,1,0,0,1,1,1,1,0,0,0. Now A118248(5) = 8, which is represented by the 1,0,0,0 at the end of the sequence. The binary representation of 9 (1001 in binary) and (decimal) 10 (1010 in binary) both occur earlier in the sequence. But the binary representation of (decimal) 11 (1011 in binary) does not occur earlier in the sequence, so (1,0,1,1) is added to the end of the sequence. And A118248(6) becomes 11.

From Michael De Vlieger, Aug 19 2017: (Start)

   n   A118248(n)  Binary digits appended to a(n)

   0           0       0

   1           1       1

   2           2      10

   3           4     100

   4           7     111

   5           8    1000

   6          11    1011

   7          16   10000

   8          18   10010

   9          21   10101

  10          22   10110

  11          25   11001

  12          29   11101

(End)

MATHEMATICA

Block[{a = {{0}}, b = {0}, k, d}, Do[k = FromDigits[#, 2] &@ Last@ a + 1; While[SequenceCount[Flatten@ a, Set[d, IntegerDigits[k, 2]]] > 0, k++]; AppendTo[a, d]; AppendTo[b, k], {i, 22}]; Flatten@ a] (* Michael De Vlieger, Aug 19 2017 *)

CROSSREFS

Cf. A118248, A118249, A118251.

Sequence in context: A143222 A010060 A316569 * A122257 A129950 A010051

Adjacent sequences:  A118244 A118245 A118246 * A118248 A118249 A118250

KEYWORD

easy,nonn,base,tabf

AUTHOR

Leroy Quet, Apr 18 2006

EXTENSIONS

More terms from Joshua Zucker, Jul 27 2006

STATUS

approved

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Last modified November 20 06:06 EST 2018. Contains 317385 sequences. (Running on oeis4.)