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 A308174 #17 May 22 2019 13:16:58 %S A308174 1,1,2,1,2,2,3,3,3,2,3,3,2,3,3,4,4,3,4,4,4,3,4,4,4,4,4,4,4,4,4,4,5,5, %T A308174 5,5,6,5,5,5,5,5,5,5,5,5,5,5,5,4,5,5,5,5,5,5,5,5,5,4,5,5,5,5,6,6,6,6, %U A308174 6,6,6,5,6,6,6,6,5,5,6,6,6,6,6,6,6,6,6 %N A308174 Let EM denote the Ehrenfeucht-Mycielski sequence A038219, and let P(n) = [EM(1),...,EM(n)]. To compute EM(n+1) for n>=3, we find the longest suffix S (say) of P(n) which has previously appeared in P(n). Suppose the most recent appearance of S began at index n-t(n). Then a(n) = length of S, while t(n) is given in A308175. %C A308174 Then EM(n+1) is the complement of the bit following the most recent appearance of S. %H A308174 Rémy Sigrist, <a href="/A308174/b308174.txt">Table of n, a(n) for n = 3..50000</a> %H A308174 Rémy Sigrist, <a href="/A308174/a308174.pl.txt">Perl program for A308174</a> %e A308174 Tableau showing calculation of terms 3 through 13 %e A308174 1 2 3 4 5 6 7 8 9 10 11 12 13 n %e A308174 0 1 0 0 1 1 0 1 0 1 1 1 0 A038219(n) %e A308174 - - 0 0 01 1 10 01 010 101 011 11 110 S %e A308174 - - 1 1 2 1 2 2 3 3 3 2 3 s = A308174(n) %e A308174 - - 1 3 1 5 2 4 1 6 4 10 5 previous %e A308174 - - 2 1 4 1 5 4 8 4 7 2 8 t = A308175(n) %e A308174 "Previous" = index of start of most recent previous occurrence of S; s = |S|; t = n - "previous" = A308175(n) %o A308174 (Perl) See Links section. %Y A308174 Cf. A038219, A308175. %K A308174 nonn %O A308174 3,3 %A A308174 _N. J. A. Sloane_, May 21 2019, corrected and extended May 21 2019 %E A308174 More terms from _Rémy Sigrist_, May 21 2019