This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A318533 #8 Sep 04 2018 15:14:09 %S A318533 1,2,3,4,5,6,10,13,9,20,21,14,8,15,7,16,60,61,50,51,40,41,30,31,24,90, %T A318533 91,80,81,70,71,62,42,25,82,63,32,17,52,35,92,72,53,26,73,43,18,46,93, %U A318533 64,27,65,19,36,83,54,100,102,94,57,95,47,84,48,74,37,75,28,58,85,38,68,96,39,59,76,103,86,29,49,69,87,104 %N A318533 Lexicographically first sequence of distinct positive integers such that a(n) + [the first digit of a(n+1)] is a palindrome in base 10. %H A318533 Jean-Marc Falcoz, <a href="/A318533/b318533.txt">Table of n, a(n) for n = 1..10001</a> %e A318533 The sequence starts with 1,2,3,4,5,6,10,13,9,... and we see that [1 + (the first digit of 2)] is a palindrome (3); [2 + (the first digit of 3)] is a palindrome (5); [3 + (the first digit of 4)] is a palindrome (7); [4 + (the first digit of 5)] is a palindrome (9); [5 + (the first digit of 6)] is a palindrome (11); [6 + (the first digit of 10)] is a palindrome (7); [10 + (the first digit of 13)] is a palindrome (11); [13 + (the first digit of 9)] is a palindrome (22); etc. %Y A318533 Cf. A318486 for a subtraction of the first digit of a(n+1) instead of the addition. %K A318533 nonn,base,look %O A318533 1,2 %A A318533 _Eric Angelini_ and _Jean-Marc Falcoz_, Aug 28 2018