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 A276757 #14 May 27 2025 10:08:22
%S A276757 1,2,3,4,5,1,2,3,1,2,3,4,5,1,2,3,4,5,1,2,3,1,2,3,4,5,1,2,3,1,2,3,4,5,
%T A276757 1,2,3,4,5,1,2,3,1,2,3,4,5,1,2,3,4,5,1,2,3,1,2,3,4,5,1,2,3,1,2,3,4,5,
%U A276757 1,2,3,4,5,1,2,3,1,2,3,4,5,1,2,3,1,2,3,4,5,1,2,3,4,5,1,2,3,1,2,3,4,5,1,2,3,4,5,1,2,3,1,2
%N A276757 Infinite Fibonacci word on the alphabet {1,2,3,4,5}.
%C A276757 Start with the infinite Fibonacci word A003849, which is 0100101001001010010... and replace each 0 by 1,2,3 and each 1 by 4,5.
%C A276757 The unique fixed point of the 4-block Fibonacci substitution 1 -> 12, 2 -> 3, 3 -> 45, 4 -> 12, 5 -> 3. Here the 4-blocks are coded as 0100 <-> 1, 1001 <-> 2, 0010 <-> 3, 0101 <-> 4, 1010 <-> 5.
%H A276757 F. Michel Dekking, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL19/Dekking/dekk4.html">Morphisms, Symbolic Sequences, and Their Standard Forms</a>, Journal of Integer Sequences, Vol. 19 (2016), Article 16.1.1.
%H A276757 Michel Dekking and Michael Keane, <a href="https://arxiv.org/abs/1608.04487">On the conjugacy class of the Fibonacci dynamical system</a>, arXiv preprint arXiv:1608.04487 [math.DS], 2016.
%F A276757 Let A(n) = floor(n*phi), B(n) = n + floor(n*phi), i.e., A and B are the lower and upper Wythoff sequences, A = A000201, B = A001950. Then a(n) = 1 if n = A(A(A(k))) for some k; a(n) = 2 if n = B(A(k)) for some k; a(n) = 3 if n = A(B(k)) for some k; a(n) = 4 if n = A(A(B(k))) for some k; a(n) = 5 if n = B(B(k)) for some k.
%Y A276757 Cf. A000201, A001950, A003849, A134859, A035336, A003623, A134860, A101864, A270788, A138967.
%K A276757 nonn
%O A276757 1,2
%A A276757 _Michel Dekking_, Sep 17 2016