A201881 - OEIS

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A201881

Run lengths in maximally unpredictable sequences A007061, A038219.

1, 1, 2, 2, 1, 1, 1, 3, 3, 1, 4, 4, 1, 2, 2, 1, 1, 1, 2, 1, 2, 3, 1, 1, 3, 2, 5, 1, 1, 2, 1, 5, 2, 2, 2, 6, 1, 1, 1, 1, 1, 2, 3, 3, 2, 1, 3, 1, 1, 1, 1, 1, 6, 2, 1, 2, 1, 1, 2, 2, 3, 1, 1, 4, 4, 1, 2, 1, 1, 2, 2, 2, 1, 3, 1, 4, 1, 1, 2, 1, 1, 1, 1, 7, 3, 2

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,3

COMMENTS

a(2*n-1) = length of n-th block of consecutive ones in A007061, or consecutive zeros in A038219;

a(2*n) = length of n-th block of consecutive twos in A007061, or consecutive ones in A038219;

a(A201882(n)) = n and a(m) < n for m < A201882(n).

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..1000

EXAMPLE

A007061: 1, 2, 1,1, 2,2, 1, 2, 1, 2,2,2, 1,1,1, 2, 1,1,1,1, 2,2,2,2, ..

A038219: 0, 1, 0,0, 1,1, 0, 1, 0, 1,1,1, 0,0,0, 1, 0,0,0,0, 1,1,1,1, ..

A201881: 1, 1, __2, __2, 1, 1, 1, ____3, ____3, 1, ______4, ______4, ...

PROG

(Haskell)

import Data.List (group)

a201881 n = a201881_list !! (n-1)

a201881_list = map length $ group a007061_list

CROSSREFS

Sequence in context: A123682 A134513 A275648 * A291120 A025485 A219365

Adjacent sequences: A201878 A201879 A201880 * A201882 A201883 A201884

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Dec 11 2011

STATUS

approved