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A273887
Pick any pair of "9" digits in the sequence. Those two "9"s are separated by k digits. This is the lexicographically earliest sequence of distinct terms in which all the resulting values of k are distinct.
2
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 30, 29, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 50, 51, 52, 49, 53, 54, 55, 56, 57, 58, 60, 61, 62, 63, 64, 59, 65, 66, 67, 68, 70, 69, 71, 72
OFFSET
1,3
COMMENTS
The sequence starts with a(1)=0. It is then always extended with the smallest integer not yet present and not leading to a contradiction (which would mean producing a value of k already seen).
LINKS
CROSSREFS
See A273376 for the equivalent sequence dealing with digit-"1" pairs instead of "9"
Sequence in context: A226537 A349294 A153679 * A194906 A160546 A356944
KEYWORD
nonn,base
AUTHOR
STATUS
approved