%I #11 Jan 22 2017 15:22:29

%S 1,2,3,5,8,13,21,4,9,17,26,43,69,112,181,23,20,63,83,10,33,53,86,11,

%T 15,37,7,6,19,25,44,94,50,22,14,36,64,28,12,16,40,24,88,32,56,120,176,

%U 296,30,38,68,106,174,34,35,103,138,241,379,46,57,149,92,333

%N Lexicographically first sequence of distinct terms with the property that each triple of consecutive terms contains a term that divides the difference of the other two terms.

%H Rémy Sigrist, <a href="/A281408/b281408.txt">Table of n, a(n) for n = 1..10000</a>

%H Rémy Sigrist, <a href="/A281408/a281408.gp.txt">PARI program for A281408</a>

%e The first terms, alongside the indexes of the terms that divides the difference of the other two terms within the n-th triple of consecutive terms, are:

%e n a(n) Indexes

%e -- ---- -------

%e 1 1 1, 2

%e 2 2 1, 2

%e 3 3 1, 2

%e 4 5 1, 2

%e 5 8 1, 2

%e 6 13 3

%e 7 21 2

%e 8 4 1

%e 9 9 1, 2

%e 10 17 1, 2

%e 11 26 1, 2

%e 12 43 1, 2

%e 13 69 1, 2

%e 14 112 3

%e 15 181 2

%e 16 23 2

%e 17 20 1, 2

%e 18 63 3

%e 19 83 2

%e 20 10 1

%e 21 33 1, 2

%e 22 53 3

%e 23 86 3

%e 24 11 1

%e 25 15 1

%Y Cf. A278962, A281409.

%K nonn

%O 1,2

%A _Rémy Sigrist_, Jan 21 2017