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 A238109 #57 Jul 02 2021 16:47:32
%S A238109 1,2,11,12,22,111,112,121,122,222,1111,1112,1121,1122,1212,1221,1222,
%T A238109 2222,11111,11112,11121,11122,11211,11212,11221,11222,12121,12122,
%U A238109 12212,12221,12222,22222,111111,111112,111121,111122,111211,111212,111221,111222,112112
%N A238109 List of prefix-normal words over the alphabet {1,2}.
%C A238109 A word of length n over the alphabet {a,b} is prefix-normal if for all 1 <= k <= n, no factor of length k has more a's than the prefix of length k. For example, abbabab is not prefix-normal because aba has more a's than abb.
%H A238109 Rémy Sigrist, <a href="/A238109/b238109.txt">Table of n, a(n) for n = 1..16906 (terms up to length 16)</a>
%H A238109 P. Burcsi, G. Fici, Zs. Lipták, F. Ruskey and J. Sawada, <a href="http://arxiv.org/abs/1401.6346">On Combinatorial Generation of Prefix Normal Words</a>, arXiv:1401.6346 [cs.DS], 2014; Combinatorial Pattern Matching 2014, Lecture Notes in Computer Science 8486, 60-69, 2014.
%H A238109 P. Burcsi, G. Fici, Zs. Lipták, F. Ruskey, and J. Sawada, <a href="https://arxiv.org/abs/1611.09017">On prefix normal words and prefix normal forms</a>, arXiv:1611.09017 [cs.DM], 2016; Theoretical Computer Science, Volume 659, 10 January 2017, Pages 1-13.
%H A238109 Ferdinando Cicalese, Zsuzsanna Lipták, and Massimiliano Rossi, <a href="https://arxiv.org/abs/1712.05876">Bubble-Flip—A new generation algorithm for prefix normal words</a>, arXiv:1712.05876 [cs.DS], 2017-2018; Theoretical Computer Science, Volume 743, 26 September 2018, Pages 38-52.
%H A238109 Ferdinando Cicalese, Zsuzsanna Lipták, and Massimiliano Rossi, <a href="https://arxiv.org/abs/1811.06273">On Infinite Prefix Normal Words</a>, arXiv:1811.06273 [math.CO], 2018.
%H A238109 G. Fici and Zs. Lipták, <a href="https://arxiv.org/abs/1805.12405">On Prefix Normal Words</a>, Developments in Language Theory 2011, Lecture Notes in Computer Science 6795, 228-238, 2011.
%H A238109 Pamela Fleischmann, <a href="https://macau.uni-kiel.de/servlets/MCRFileNodeServlet/macau_derivate_00002273/diss.pdf">On Special k-Spectra, k-Locality, and Collapsing Prefix Normal Words</a>, Ph.D. Dissertation, Kiel University (Germany, 2021).
%H A238109 Pamela Fleischmann, Mitja Kulczynski, and Dirk Nowotka, <a href="https://arxiv.org/abs/1905.11847">On Collapsing Prefix Normal Words</a>, arXiv:1905.11847 [cs.FL], 2019.
%H A238109 Pamela Fleischmann, Mitja Kulczynski, Dirk Nowotka, and Danny Bøgsted Poulsen, <a href="https://doi.org/10.1007/978-3-030-40608-0_29">On Collapsing Prefix Normal Words</a>, Language and Automata Theory and Applications (LATA 2020) LNCS Vol. 12038, Springer, Cham, 412-424.
%H A238109 Zsuzsanna Lipták, <a href="http://profs.scienze.univr.it/~liptak/files/OpenProblemsPNW.pdf">Open problems on prefix normal words</a>, also in <a href="http://drops.dagstuhl.de/opus/volltexte/2019/10178/">Dagstuhl Reports</a> (2018) Vol. 8, Issue 7, 59-61.
%Y A238109 Cf. A194850.
%K A238109 nonn
%O A238109 1,2
%A A238109 _N. J. A. Sloane_, Mar 02 2014
%E A238109 More terms from _Rémy Sigrist_, Feb 12 2017