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The rightmost digit d of a(n) jumps over d digits to the right and is duplicated there. Lexicographically earliest sequence of distinct positive integers with this property.
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%I #16 Aug 01 2020 15:54:16

%S 1,2,11,21,3,12,4,322,5,42,6,7,251,8,161,71,9,13,82,1322,19,22,14,24,

%T 15,49,43,151,31,41,91,51,61,81,111,112,16,23,17,33,62,53,27,63,18,73,

%U 37,83,25,831,715,26,28,35,29,64,158,34,36,93,44

%N The rightmost digit d of a(n) jumps over d digits to the right and is duplicated there. Lexicographically earliest sequence of distinct positive integers with this property.

%C No term ends in 0 as this would force the next integer to start with zero.

%H Carole Dubois, <a href="/A336034/b336034.txt">Table of n, a(n) for n = 1..5000</a>

%e The rightmost digit of a(1) = 1 is 1; we duplicate this digit in position 3;

%e The rightmost digit of a(2) = 2 is 2; we duplicate this digit in position 5;

%e The rightmost digit of a(3) = 11 is 1; we duplicate this digit in position 6;

%e The rightmost digit of a(4) = 21 is 1; we duplicate this digit in position 8;

%e The rightmost digit of a(5) = 3 is 3; we duplicate this digit in position 11; etc.

%Y Cf. A336035 (duplication of the leftmost digit of a(n) to the left), A336036 (first and last digits of a(n) are duplicated respectively to the left and to the right).

%K base,nonn

%O 1,2

%A _Eric Angelini_ and _Carole Dubois_, Jul 05 2020