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 A144569 #11 Jul 26 2025 10:19:55 %S A144569 0,0,0,1,1,1,0,1,0,0,2,0,2,2,2,1,2,1,1,2,2,0,0,3,0,3,3,3,2,3,2,2,3,3, %T A144569 1,3,1,1,3,3,0,1,3,2,0,3,2,1,0,3,1,0,2,3,1,2,0,1,2,3,0,2,1,3,0,0,0,1, %U A144569 1,1,0,1,0,0,2,0,2,2,2,1,2,1,1,2,2,0,0,3,0,3,3,3,2,3,2,2,3,3,1 %N A144569 A de Bruijn sequence B(4,3) found by Ted Bell. %H A144569 Mark Dow, <a href="https://web.archive.org/web/20140527202958/http://lcni.uoregon.edu/~dow/Geek_art/Minimal_combinatorics/Minimal_arrays_containing_all_combinations.html">Minimal arrays containing all sub-array combinations of symbols: de Bruijn sequences and tori</a> (Web archive) %H A144569 Wikipedia, <a href="http://en.wikipedia.org/wiki/De_Bruijn_sequence">De Bruijn Sequences</a> %H A144569 <a href="/index/Rec#order_64">Index entries for linear recurrences with constant coefficients</a>, order 64. %e A144569 Period 64: 0001110100202221211220030333232233131133013203210310231201230213 %Y A144569 A135472 gives an example of a B(9,2). %Y A144569 Cf. also A080679, A058342, A083570, A166315, A166316. %K A144569 nonn,easy %O A144569 0,11 %A A144569 _N. J. A. Sloane_, Apr 09 2010, based on a communication from David Paterson (David.Paterson(AT)csiro.au)