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A308173
Take the list of all binary vectors (including those beginning with 0) in lexicographic order; a(n) is the index of the first occurrence of the n-th binary vector as a subsequence of A038219.
2
1, 2, 3, 1, 2, 5, 13, 3, 1, 4, 2, 6, 5, 10, 17, 13, 14, 3, 1, 7, 4, 9, 12, 2, 6, 8, 11, 5, 10, 21, 48, 17, 13, 18, 14, 28, 3, 19, 15, 1, 29, 7, 25, 4, 9, 20, 16, 12, 27, 2, 30, 6, 24, 8, 11, 26, 5, 23, 10, 22, 21, 58, 99, 48, 49, 17, 13, 50, 43, 18, 14, 33, 28
OFFSET
1,2
COMMENTS
Ehrenfeucht and Mycielski (1992) prove that every binary vector appears in A038219, so the sequence is well-defined.
LINKS
A. Ehrenfeucht and J. Mycielski, A pseudorandom sequence - how random is it?, Amer. Math. Monthly, 99 (1992), 373-375.
EXAMPLE
A038219 begins 0, 1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 0, ... and has offset 1. Here is the start of the list of binary vectors and the index where they first appear in the sequence:
0: 1
1: 2
00: 3
01: 1
10: 2
11: 5
000: 13
001: 3
...
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, May 20 2019
EXTENSIONS
More terms from Rémy Sigrist, May 21 2019
STATUS
approved