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A102234
Slowest increasing sequence such that no digit "d" has a copy of itself at "d" digits, left or right.
0
1, 2, 3, 4, 5, 6, 7, 8, 9, 12, 13, 14, 15, 16, 17, 18, 19, 21, 31, 32, 34, 35, 36, 37, 38, 39, 41, 42, 51, 52, 53, 54, 56, 57, 58, 59, 61, 62, 63, 71, 72, 73, 74, 75, 76, 78, 79, 81, 82, 83, 84, 121, 312, 412
OFFSET
1,2
EXAMPLE
Take integer [78] in the sequence for instance : ...73 74 75 76 [78] 79 81 82 83...
The digit "7", jumping 7 digits back, ends on "3" [73] which is not "7"; jumping 7 digits to the right ends on "2" which, again, is not a "7". The same can be said for "8" (left -> "7"; right -> "3")
CROSSREFS
Subsequence of A052382.
Cf. A102150.
Sequence in context: A039274 A102487 A343951 * A174908 A344543 A082757
KEYWORD
base,easy,nonn
AUTHOR
Eric Angelini, Feb 18 2005
STATUS
approved