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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. 3
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, 17, 25, 27, 19, 34, 9, 23, 7, 38, 21, 32, 20, 38, 14, 30, 34, 29, 45, 24, 39, 35, 4, 36, 41, 27, 49, 33, 54, 36, 52, 41, 4, 42, 54, 39, 31, 65, 24, 44, 9, 36, 53 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,1

COMMENTS

Then EM(n+1) is the complement of the bit following the most recent appearance of S.

LINKS

Rémy Sigrist, Table of n, a(n) for n = 3..50000

Rémy Sigrist, Perl program for A308175

EXAMPLE

Tableau showing calculation of terms 3 through 13

1   2   3   4   5   6   7   8   9  10  11  12  13  n

0   1   0   0   1   1   0   1   0   1   1   1   0  A038219(n)

-   -   0   0  01   1  10  01 010 101 011  11 110  S

-   -   1   1   2   1   2   2   3   3   3   2   3  s = A308174(n)

-   -   1   3   1   5   2   4   1   6   4  10   5  previous

-   -   2   1   4   1   5   4   8   4   7   2   8  t = A308175(n)

"Previous" = index of start of most recent previous occurrence of S; s = |S|; t = n - "previous" = A308175(n)

PROG

(Perl) See Links section.

CROSSREFS

Cf. A038219, A308174.

Sequence in context: A218970 A216952 A114326 * A241423 A323244 A329642

Adjacent sequences:  A308172 A308173 A308174 * A308176 A308177 A308178

KEYWORD

nonn,look

AUTHOR

N. J. A. Sloane, May 21 2019, corrected and extended May 21 2019

EXTENSIONS

More terms from Rémy Sigrist, May 21 2019

STATUS

approved

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Last modified September 29 18:27 EDT 2020. Contains 337432 sequences. (Running on oeis4.)