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Slowest increasing sequence such that no digit "d" from any a(n) has a copy of itself in a(n+d), left or right.
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%I #3 Mar 31 2012 13:46:51

%S 1,2,3,4,5,6,7,8,9,11,22,23,31,33,41,52,54,55,56,57,61,62,63,64,71,72,

%T 81,83,84,85,86,88,89,91,92,93,94,95,96,97,99,111,222,223,311,333,411,

%U 421,424,431,533,535,551,552,554,611,622,623,631,633,641,722,724

%N Slowest increasing sequence such that no digit "d" from any a(n) has a copy of itself in a(n+d), left or right.

%e Take integer [41] in the sequence, for instance : ...22 23 31 33 [41] 52 54 55 56.

%e The digit "4", jumping 4 integers back, ends on [22] which has no "4"; jumping 4 digits to the right ends on [56] which, again, has no "4". The same can be said for "1" (left -> [33]; right ->[52])

%Y Cf. A102150.

%K base,easy,nonn

%O 1,2

%A _Eric Angelini_, Feb 18 2005