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 A305394 #34 Jun 26 2022 22:45:11
%S A305394 5,4,5,3,5,4,5,5,4,5,3,5,4,5,4,5,3,5,4,5,5,4,5,3,5,4,5,3,5,4,5,5,4,5,
%T A305394 3,5,4,5,4,5,3,5,4,5,5,4,5,3,5,4,5,5,4,5,3,5,4,5,4,5,3,5,4,5,5,4,5,3,
%U A305394 5,4,5,3,5,4,5,5,4,5,3,5,4,5,4,5,3,5,4,5,5,4,5,3,5,4,5,4
%N A305394 First differences of A140103.
%C A305394 Conjecture: this sequence is the ternary tribonacci word on the alphabet {5,4,3}, i.e., (a(n)) is the unique fixed point of the morphism 5 -> 54, 4 -> 53, 3 -> 5; see A092782. - _Michel Dekking_, Mar 13 2019
%C A305394 An equivalent conjecture: This sequence (prefixed by 3 since A140103 should really begin with 0) is 3.TTW(5,4,3) where TTW is the ternary tribonacci word defined in A080843, or equally it is THETA(5,4,3), where THETA is defined in A275925. There are similar conjectures for the first differences of A140100, A140101, A140102. - _N. J. A. Sloane_, Mar 14 2019 and Mar 19 2019
%C A305394 All these conjectures are now theorems - see the Dekking et al. paper. - _N. J. A. Sloane_, Jul 22 2019
%H A305394 N. J. A. Sloane, <a href="/A305394/b305394.txt">Table of n, a(n) for n = 1..49999</a>F.
%H A305394 Michel Dekking, Jeffrey Shallit, and N. J. A. Sloane, <a href="https://www.combinatorics.org/ojs/index.php/eljc/article/view/v27i1p52/8039">Queens in exile: non-attacking queens on infinite chess boards</a>, Electronic J. Combin., 27:1 (2020), #P1.52.
%F A305394 a(n) = A140103(n+1) - A140103(n).
%Y A305394 For first differences of A140100, A140101, A140102, A140103 see A305392, A305374, A305393, A305394.
%K A305394 nonn
%O A305394 1,1
%A A305394 _N. J. A. Sloane_, Jun 23 2018