# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a281408 Showing 1-1 of 1 %I A281408 #11 Jan 22 2017 15:22:29 %S A281408 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 A281408 15,37,7,6,19,25,44,94,50,22,14,36,64,28,12,16,40,24,88,32,56,120,176, %U A281408 296,30,38,68,106,174,34,35,103,138,241,379,46,57,149,92,333 %N A281408 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 A281408 Rémy Sigrist, Table of n, a(n) for n = 1..10000 %H A281408 Rémy Sigrist, PARI program for A281408 %e A281408 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 A281408 n a(n) Indexes %e A281408 -- ---- ------- %e A281408 1 1 1, 2 %e A281408 2 2 1, 2 %e A281408 3 3 1, 2 %e A281408 4 5 1, 2 %e A281408 5 8 1, 2 %e A281408 6 13 3 %e A281408 7 21 2 %e A281408 8 4 1 %e A281408 9 9 1, 2 %e A281408 10 17 1, 2 %e A281408 11 26 1, 2 %e A281408 12 43 1, 2 %e A281408 13 69 1, 2 %e A281408 14 112 3 %e A281408 15 181 2 %e A281408 16 23 2 %e A281408 17 20 1, 2 %e A281408 18 63 3 %e A281408 19 83 2 %e A281408 20 10 1 %e A281408 21 33 1, 2 %e A281408 22 53 3 %e A281408 23 86 3 %e A281408 24 11 1 %e A281408 25 15 1 %Y A281408 Cf. A278962, A281409. %K A281408 nonn %O A281408 1,2 %A A281408 _Rémy Sigrist_, Jan 21 2017 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE