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 A343484 #13 Apr 17 2021 14:31:11
%S A343484 0,1,1,2,3,5,8,13,18,27,41,62,90,134,198,293,423,619,908,1329,1938,
%T A343484 2832,4142,6061,8824,12879,18794,27425,39977,58333,85109,124180,
%U A343484 180994,263931,384933,561402,818617,1193841,1740980,2538896,3702022,5398458,7872351
%N A343484 Number of equivalence classes of length n squarefree reduced words over {0, 1, 2, 3} under action of renaming symbols.
%C A343484 Any equivalence class of words with length at least 2 has exactly 8 members.
%H A343484 Richard A. Dean, <a href="http://www.jstor.org/stable/2313498">A sequence without repeats on x, x^{-1}, y, y^{-1}</a>, Amer. Math. Monthly 72, 1965. pp. 383-385. MR 31 #350.
%H A343484 Tero Harju, <a href="https://arxiv.org/abs/2104.06837">Avoiding Square-Free Words on Free Groups</a>, arXiv:2104.06837 [math.CO], 2021.
%F A343484 a(n) = A343421(n)/8 for n >= 2.
%e A343484 a(5) = 5 corresponds to the 5 words 01210, 01030, 01230, 01032, and 01232.
%Y A343484 Cf. A215075, A343421.
%K A343484 nonn
%O A343484 0,4
%A A343484 _James Rayman_, Apr 16 2021