cp's OEIS Frontend

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.

A308175 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) = t(n), while the length of S is given in A308174.

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%I A308175 #17 May 22 2019 13:17:54
%S A308175 2,1,4,1,5,4,8,4,7,2,8,12,2,13,10,17,7,3,8,19,14,3,15,21,19,24,18,28,
%T A308175 17,25,27,19,34,9,23,7,38,21,32,20,38,14,30,34,29,45,24,39,35,4,36,41,
%U A308175 27,49,33,54,36,52,41,4,42,54,39,31,65,24,44,9,36,53
%N A308175 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) = t(n), while the length of S is given in A308174.
%C A308175 Then EM(n+1) is the complement of the bit following the most recent appearance of S.
%H A308175 Rémy Sigrist, <a href="/A308175/b308175.txt">Table of n, a(n) for n = 3..50000</a>
%H A308175 Rémy Sigrist, <a href="/A308175/a308175.pl.txt">Perl program for A308175</a>
%e A308175 Tableau showing calculation of terms 3 through 13
%e A308175 1   2   3   4   5   6   7   8   9  10  11  12  13  n
%e A308175 0   1   0   0   1   1   0   1   0   1   1   1   0  A038219(n)
%e A308175 -   -   0   0  01   1  10  01 010 101 011  11 110  S
%e A308175 -   -   1   1   2   1   2   2   3   3   3   2   3  s = A308174(n)
%e A308175 -   -   1   3   1   5   2   4   1   6   4  10   5  previous
%e A308175 -   -   2   1   4   1   5   4   8   4   7   2   8  t = A308175(n)
%e A308175 "Previous" = index of start of most recent previous occurrence of S; s = |S|; t = n - "previous" = A308175(n)
%o A308175 (Perl) See Links section.
%Y A308175 Cf. A038219, A308174.
%K A308175 nonn,look
%O A308175 3,1
%A A308175 _N. J. A. Sloane_, May 21 2019, corrected and extended May 21 2019
%E A308175 More terms from _Rémy Sigrist_, May 21 2019