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A308406
Lexicographically earliest sequence of distinct terms such that reading one-by-one the central digit of each term is the same as reading one-by-one the successive digits of the sequence itself.
2
1, 2, 3, 4, 5, 6, 7, 8, 9, 110, 111, 100, 112, 113, 114, 115, 101, 102, 116, 117, 120, 118, 119, 130, 210, 211, 140, 212, 213, 150, 214, 103, 215, 216, 104, 121, 217, 218, 160, 219, 310, 170, 311, 122, 105, 312, 313, 180, 314, 315, 190, 316, 131, 106, 123, 317
OFFSET
1,2
COMMENTS
All terms of the sequence have an odd number of digits. For terms having only an even number of digits, see the Cross-references section.
LINKS
EXAMPLE
The "central digit" of 1 is 1, of course. The central digit of 100 is 0, the central digit of 123 is 2, etc. Reading the successive central digits of the successive terms produces 1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 1, 0, 1, 1, 1, 1, 0, 0, sequence, which are exactly the successive digits of the sequence itself.
CROSSREFS
Cf. A308407 (the same idea, but with terms having an even number of digits).
Sequence in context: A302656 A077726 A061479 * A028431 A181352 A056143
KEYWORD
base,nonn
AUTHOR
Eric Angelini, May 25 2019
EXTENSIONS
More terms from Lars Blomberg, May 26 2019
STATUS
approved