A302663 - OEIS

%I #8 Apr 11 2018 16:23:01

%S 1,2,4,7,3,8,14,21,13,22,11,33,66,110,55,121,44,132,231,130,19,140,9,

%T 150,301,462,291,472,281,483,271,493,261,503,251,513,241,523,815,512,

%U 199,522,189,532,179,542,169,552,159,563,149,573,139,583,129,593,119,603,109,614,99,624,89,634,79,644

%N Lexicographically first sequence of distinct terms such that the absolute differences |a(n) - a(n+1)| are A002113(n+1), where A002113 is "the palindromes in base 10".

%C The sequence starts with a(1) = 1 and is always extended with the smallest integer not yet present that doesn't lead to a contradiction.

%H Jean-Marc Falcoz, <a href="/A302663/b302663.txt">Table of n, a(n) for n = 1..2229</a>

%e |1 - 2| = 1, which is the 2nd palindrome of A002113 (the 1st one being "0");

%e |2 - 4| = 2 which is the 3rd palindrome;

%e |4 - 7| = 3 which is the 4th palindrome;

%e |7 - 3| = 4 which is the 5th palindrome;

%e |3 - 8| = 5 which is the 6th palindrome;

%e |8 - 14| = 6 which is the 7th palindrome;

%e |14 - 21| = 7 which is the 8th palindrome;

%e |21 - 13| = 8 which is the 9th palindrome;

%e |13 - 22| = 9 which is the 10th palindrome;

%e |22 - 11| = 11 which is the 11th palindrome;

%e |11 - 33| = 22 which is the 12th palindrome; etc.

%Y Cf. A002113 (palindromes in base 10).

%K nonn,base

%O 1,2

%A _Eric Angelini_ and _Jean-Marc Falcoz_, Apr 11 2018