%I #12 Feb 24 2021 08:54:17
%S 1,9,10,2,8,4,14,20,11,3,17,13,5,6,7,12,15,16,18,27,19,28,23,29,22,30,
%T 21,25,26,32,40,31,50,39,33,35,37,36,46,43,49,53,60,41,51,52,68,47,45,
%U 24,59,61,63,38,55,48,57,44,69,70,62,71,42,73,58,79,34,72,74,82,64,66,75,54,81,56,80
%N Lexicographically earliest sequence of distinct terms > 0 such that the n-th digit of the sequence is present in a(n) + a(n+1).
%H Carole Dubois, <a href="/A341818/b341818.txt">Table of n, a(n) for n = 1..5000</a>
%e The 1st digit of the sequence [1] is present in a(1) + a(2) = 1 + 9 = 10;
%e the 2nd digit of the sequence [9] is present in a(2) + a(3) = 9 + 10 = 19;
%e the 3rd digit of the sequence [1] is present in a(3) + a(4) = 10 + 2 = 12;
%e the 4th digit of the sequence [0] is present in a(4) + a(5) = 2 + 8 = 10;
%e the 5th digit of the sequence [2] is present in a(5) + a(6) = 8 + 4 = 12;
%e the 6th digit of the sequence [8] is present in a(6) + a(7) = 4 + 14 = 18;
%e the 7th digit of the sequence [4] is present in a(7) + a(8) = 14 + 20 = 34;
%e etc.
%Y Cf. A341819 (absolute difference), A341820 (product), A341821 (cumulative sum).
%K base,nonn
%O 1,2
%A _Eric Angelini_ and _Carole Dubois_, Feb 20 2021