A010060 -id:A010060 - cp's OEIS frontend

A026465 Length of n-th run of identical symbols in the Thue-Morse sequence A010060 (or A001285).

1, 2, 1, 1, 2, 2, 2, 1, 1, 2, 1, 1, 2, 1, 1, 2, 2, 2, 1, 1, 2, 2, 2, 1, 1, 2, 2, 2, 1, 1, 2, 1, 1, 2, 1, 1, 2, 2, 2, 1, 1, 2, 1, 1, 2, 1, 1, 2, 2, 2, 1, 1, 2, 1, 1, 2, 1, 1, 2, 2, 2, 1, 1, 2, 2, 2, 1, 1, 2, 2, 2, 1, 1, 2, 1, 1, 2, 1, 1, 2, 2, 2, 1, 1, 2, 2, 2, 1, 1, 2, 2, 2, 1, 1, 2, 1, 1, 2, 1, 1, 2, 2, 2, 1, 1

Offset: 1

Clark Kimberling

It appears that the sequence can be calculated by any of the following methods:
(1) Start with 1 and repeatedly replace 1 with 1, 2, 1 and 2 with 1, 2, 2, 2, 1;
(2) a(1) = 1, all terms are either 1 or 2 and, for n > 0, a(n) = 1 if the length of the n-th run of 2's is 1; a(n) = 2 if the length of the n-th run of consecutive 2's is 3, with each run of 2's separated by a run of two 1's;
(3) replace each 3 in A080426 with 2. - John W. Layman, Feb 18 2003
Number of representations of n as a sum of Jacobsthal numbers (1 is allowed twice as a part). Partial sums are A003159. With interpolated zeros, g.f. is (Product_{k>=1} (1 + x^A078008(k)))/2. - Paul Barry, Dec 09 2004
In other words, the consecutive 0's or 1's in A010060 or A010059. - Robin D. Saunders (saunders_robin_d(AT)hotmail.com), Sep 06 2006
From Carlo Carminati, Feb 25 2011: (Start)
The sequence (starting with the second term) can also be calculated by the following method:
Apply repeatedly to the string S_0 = [2] the following algorithm: take a string S, double it, if the last figure is 1, just add the last figure to the previous one, if the last figure is greater than one, decrease it by one unit and concatenate a figure 1 at the end. (This algorithm is connected with the interpretation of the sequence as a continued fraction expansion.) (End)
This sequence, starting with the second term, happens to be the continued fraction expansion of the biggest cluster point of the set {x in [0,1]: F^k(x) >= x, for all k in N}, where F denotes the Farey map (see A187061). - Carlo Carminati, Feb 28 2011
Starting with the second term, the fixed point of the substitution 2 -> 211, 1 -> 2. - Carlo Carminati, Mar 03 2011
It appears that this sequence contains infinitely many distinct palindromic subsequences. - Alexander R. Povolotsky, Oct 30 2016
From Michel Dekking, Feb 13 2019: (Start)
Let tau defined by tau(0) = 01, tau(1) = 10 be the Thue-Morse morphism, with fixed point A010060. Consecutive runs in A010060 are 0, 11, 0, 1, 00, 1, 1, ..., which are coded by their lengths 1, 2, 1, 1, 2, ... Under tau^2 consecutive runs are mapped to consecutive runs:
      tau^2(0) = 0110, tau^2(1) = 1001,
      tau^2(00) = 01100110, tau^2(11) = 10011001.
The reason is that (by definition of a run!) runs of 0's and runs of 1's alternate in the sequence of runs, and this is inherited by the image of these runs under tau^2.
Under tau^2 the runs of length 1 are mapped to the sequence 1,2,1 of run lengths, and the runs of length 2 are mapped to the sequence 1,2,2,2,1 of run lengths. This proves John Layman's conjecture number (1): it follows that (a(n)) is fixed point of the morphism alpha
      alpha: 1 -> 121, 2 -> 12221.
Since alpha(1) and alpha(2) are both palindromes, this also proves Alexander Povolotsky's conjecture.
(End)

N. J. A. Sloane, Table of n, a(n) for n = 1..10000
G. Allouche, Jean-Paul Allouche and Jeffrey Shallit, Kolam indiens, dessins sur le sable aux îles Vanuatu, courbe de Sierpinski et morphismes de monoïde, Ann. Inst. Fourier (Grenoble), Vol. 56, No. 7 (2006), pp. 2115-2130.
Jean-Paul Allouche, On the morphism 1 -> 121, 2 -> 12221, CNRS France, 2024. See pp. 1-3, 7.
Jean-Paul Allouche, On the morphism 1 -> 121, 2 -> 12221, Preprint, 2024 [Local copy, with permission]
Jean-Paul Allouche, Andre Arnold, Jean Berstel, Srecko Brlek, William Jockusch, Simon Plouffe and Bruce E. Sagan, A sequence related to that of Thue-Morse, Discrete Math., Vol. 139, No. 1-3 (1995), pp. 455-461.
Claudio Bonanno, Carlo Carminati, Stefano Isola and Giulio Tiozzo, Dynamics of continued fractions and kneading sequences of unimodal maps, arXiv:1012.2131 [math.DS], 2010-2012.
Srećko Brlek, Enumeration of factors in the Thue-Morse word, Discrete Applied Math., Vol. 24, No. 1-3 (1989), pp. 83-96.
Julien Cassaigne, Limit values of the recurrence quotient of Sturmian sequences, Theoret. Comput. Sci., Vol. 218, No. 1 (1999), pp. 3-12.
Artūras Dubickas, On the distance from a rational power to the nearest integer, Journal of Number Theory, Vol. 117, No. 1 (March 2006), pp. 222-239.
Artūras Dubickas, On a sequence related to that of Thue-Morse and its applications, Discrete Math., Vol. 307, No. 9-10 (2007), pp. 1082-1093. MR2292537 (2008b:11086).
Cor Kraaikamp, Thomas A. Schmidt and Wolfgang Steiner, Natural extensions and entropy of alpha-continued fractions, arXiv:1011.4283 [math.DS], 2010-2012.
Claude Lenormand, Deux transformations sur les mots, Preprint, 5 pages, Nov 17 2003. Apparently unpublished. This is a scanned copy of the version that the author sent to me in 2003. - _N. J. A. Sloane_, Sep 09 2018. See page 2.
Kevin Ryde, PARI/GP Code
Jeffrey Shallit, Automaticity IV: Sequences, sets, and diversity, J. Théor. Nombres Bordeaux, Vol. 8, No. 2 (1996), pp. 347-367. See page 354.

Cf. A010060, A001285, A101615, A026490 (run lengths).
A080426 is an essentially identical sequence with another set of constructions.
Cf. A104248 (bisection odious), A143331 (bisection evil), A003159 (partial sums).
Cf. A187061, A363361 (as continued fraction).

import Data.List (group)
a026465 n = a026465_list !! (n-1)
a026465_list = map length $ group a010060_list
-- Reinhard Zumkeller, Jul 15 2014

# From Carlo Carminati, Feb 25 2011:
## period-doubling routine:
double:=proc(SS)
NEW:=[op(S), op(S)]:
if op(nops(NEW),NEW)=1
then NEW:=[seq(op(j,NEW), j=1..nops(NEW)-2),op(nops(NEW)-1,NEW)+1]:
else NEW:=[seq(op(j,NEW), j=1..nops(NEW)-1),op(nops(NEW)-1,NEW)-1,1]:
fi:
end proc:
# 10 loops of the above routine generate the first 1365 terms of the sequence
# (except for the initial term):
S:=[2]:
for j from 1 to 10  do S:=double(S); od:
S;
# From N. J. A. Sloane, Dec 31 2013:
S:=[b]; M:=14;
for n from 1 to M do T:=subs({b=[b,a,a], a=[b]}, S);
    S := map(x->op(x),T); od:
T:=subs({a=1,b=2},S): T:=[1,op(T)]: [seq(T[n],n=1..40)];

Length /@ Split@ Nest[ Flatten@ Join[#, # /. {1 -> 2, 2 -> 1}] &, {1}, 7]
NestList[ Flatten[# /. {1 -> {2}, 2 -> {1, 1, 2}}] &, {1}, 7] // Flatten (* Robert G. Wilson v, May 20 2014 *)

PARI
```
\\ See links.
```

def A026465(n):
    if n==1: return 1
    def iterfun(f,n=0):
        m, k = n, f(n)
        while m != k: m, k = k, f(k)
        return m
    def f(x):
        c, s = x, bin(x)[2:]
        l = len(s)
        for i in range(l&1^1,l,2):
            c -= int(s[i])+int('0'+s[:i],2)
        return c
    return iterfun(lambda x:f(x)+n,n)-iterfun(lambda x:f(x)+n-1,n-1) # Chai Wah Wu, Jan 29 2025

a(1) = 1; for n > 1, a(n) = A003159(n) - A003159(n-1). - Benoit Cloitre, May 31 2003
G.f.: Product_{k>=1} (1 + x^A001045(k)). - Paul Barry, Dec 09 2004
Asymptotic mean: lim_{m->oo} (1/m) * Sum_{k=1..m} a(k) = 3/2. - Amiram Eldar, Jan 16 2022

Corrected and extended by John W. Layman, Feb 18 2003

Definition revised by N. J. A. Sloane, Dec 30 2013

A115384 Partial sums of Thue-Morse numbers A010060.

Original entry on oeis.org

0, 1, 2, 2, 3, 3, 3, 4, 5, 5, 5, 6, 6, 7, 8, 8, 9, 9, 9, 10, 10, 11, 12, 12, 12, 13, 14, 14, 15, 15, 15, 16, 17, 17, 17, 18, 18, 19, 20, 20, 20, 21, 22, 22, 23, 23, 23, 24, 24, 25, 26, 26, 27, 27, 27, 28, 29, 29, 29, 30, 30, 31, 32, 32, 33, 33, 33, 34, 34, 35, 36, 36, 36, 37, 38, 38

Offset: 0

Paul Barry, Jan 21 2006

G. C. Greubel, Table of n, a(n) for n = 0..10000
Hassan Tarfaoui, Concours Général 1990 - Exercice 1 (in French).
Index to sequences related to Olympiads and other Mathematical competitions.

Cf. A000069, A000120, A010060, A026430, A115382, A159481.

Accumulate[Nest[Flatten[#/.{0->{0,1},1->{1,0}}]&,{0},7]] (* Peter J. C. Moses, Apr 15 2013 *)
Accumulate[ThueMorse[Range[0,100]]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Jun 02 2017 *)

a(n)=n\2 + (n%2 || hammingweight(n+1)%2==0) \\ Charles R Greathouse IV, Mar 22 2013

def A115384(n): return (n>>1)+(n&1|((n+1).bit_count()&1^1)) # Chai Wah Wu, Mar 01 2023

a(n) = Sum_{k=0..n} A010060(k)^2.
a(n+1) = A115382(2n, n).
a(n)/n -> 1/2; a(n) = number of odious numbers <= n, see A000069. - Reinhard Zumkeller, Aug 26 2007, corrected by M. F. Hasler, May 22 2017.
a(n) = Sum_{i=1..n} (S2(n) mod 2), where S2 = binary weight; lim a(n)/n = 1/2. More generally, consider a(n) = Sum_{i=1..n} (F(Sk(n)) mod m), where Sk(n) is sum of digits of n, n in base k; F(t) is an arithmetic function; m integer. How does lim a(n)/n depend on F(t)? - Ctibor O. Zizka, Feb 25 2008
a(n) = n + 1 - A159481(n). - Reinhard Zumkeller, Apr 16 2009
a(n) = floor((n+1)/2)+(1+(-1)^n)*(1-(-1)^A000120(n))/4. - Vladimir Shevelev, May 27 2009
G.f.: (1/(1 - x)^2 - Product_{k>=1} (1 - x^(2^k)))/2. - Ilya Gutkovskiy, Apr 03 2019
a(n) = A026430(n+1) - n - 1. - Michel Dekking, Sep 17 2019
a(2n+1) = n+1 (see Hassan Tarfaoui link, Concours Général 1990). - Bernard Schott, Jan 21 2022

Edited by M. F. Hasler, May 22 2017

A316828 Image of the Thue-Morse sequence A010060 under the morphism {1 -> 1,2; 0 -> 0,2}.

Original entry on oeis.org

0, 2, 1, 2, 1, 2, 0, 2, 1, 2, 0, 2, 0, 2, 1, 2, 1, 2, 0, 2, 0, 2, 1, 2, 0, 2, 1, 2, 1, 2, 0, 2, 1, 2, 0, 2, 0, 2, 1, 2, 0, 2, 1, 2, 1, 2, 0, 2, 0, 2, 1, 2, 1, 2, 0, 2, 1, 2, 0, 2, 0, 2, 1, 2, 1, 2, 0, 2, 0, 2, 1, 2, 0, 2, 1, 2, 1, 2, 0, 2, 0, 2, 1, 2, 1, 2, 0, 2, 1, 2, 0, 2, 0, 2, 1, 2, 0, 2, 1, 2, 1, 2, 0, 2, 1, 2

Offset: 0

N. J. A. Sloane, Jul 14 2018

nonn

The morphism is applied just once.
This is a word that is pure morphic and uniform primitive morphic, but neither pure uniform morphic nor pure primitive morphic.
A010060 interleaved with A007395. - Antti Karttunen, Oct 08 2018

Antti Karttunen, Table of n, a(n) for n = 0..65537
Jean-Paul Allouche, Julien Cassaigne, Jeffrey Shallit, and Luca Q. Zamboni, A Taxonomy of Morphic Sequences, arXiv:1711.10807 [cs.FL], 2017.

Cf. A010060.

Sequences mentioned in the Allouche et al. "Taxonomy" paper, listed by example number: 1: A003849, 2: A010060, 3: A010056, 4: A020985 and A020987, 5: A191818, 6: A316340 and A273129, 18: A316341, 19: A030302, 20: A063438, 21: A316342, 22: A316343, 23: A003849 minus its first term, 24: A316344, 25: A316345 and A316824, 26: A020985 and A020987, 27: A316825, 28: A159689, 29: A049320, 30: A003849, 31: A316826, 32: A316827, 33: A316828, 34: A316344, 35: A043529, 36: A316829, 37: A010060.

Riffle[ThueMorse[Range[0,100]],2] (* Paolo Xausa, Dec 18 2023 *)

A316828(n) = if(n%2,2,hammingweight(n/2)%2); \\ Antti Karttunen, Oct 08 2018

If n is odd, a(n) = 2, otherwise a(n) = A010060(n/2). - Antti Karttunen, Oct 08 2018

A014571 Consider the Morse-Thue sequence (A010060) as defining a binary constant and convert it to decimal.

Original entry on oeis.org

4, 1, 2, 4, 5, 4, 0, 3, 3, 6, 4, 0, 1, 0, 7, 5, 9, 7, 7, 8, 3, 3, 6, 1, 3, 6, 8, 2, 5, 8, 4, 5, 5, 2, 8, 3, 0, 8, 9, 4, 7, 8, 3, 7, 4, 4, 5, 5, 7, 6, 9, 5, 5, 7, 5, 7, 3, 3, 7, 9, 4, 1, 5, 3, 4, 8, 7, 9, 3, 5, 9, 2, 3, 6, 5, 7, 8, 2, 5, 8, 8, 9, 6, 3, 8, 0, 4, 5, 4, 0, 4, 8, 6, 2, 1, 2, 1, 3, 3, 3, 9, 6, 2, 5, 6

Offset: 0

Eric W. Weisstein

This constant is transcendental (Mahler, 1929). - Amiram Eldar, Nov 14 2020

			0.412454033640107597783361368258455283089...
In hexadecimal, .6996966996696996... .

Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 6.8 Prouhet-Thue-Morse Constant, p. 437.

Harry J. Smith, Table of n, a(n) for n = 0..20000
Boris Adamczewski and Yann Bugeaud, A short proof of the transcendence of Thue-Morse continued fractions, The American Mathematical Monthly, Vol. 114, No. 6 (2007), pp. 536-540; alternative link.
Jean-Paul Allouche and Jeffrey Shallit, The ubiquitous Prouhet-Thue-Morse sequence, in: C. Ding, T. Helleseth, and H. Niederreiter (eds.), Sequences and their applications, Springer, London, 1999, pp. 1-16; alternative link.
Joerg Arndt, Matters Computational (The Fxtbook), p.726 ff.
Michel Dekking, Transcendance du nombre de Thue-Morse, Comptes Rendus de l'Academie des Sciences de Paris, Série A, Vol. 285 (1977) A157-A160.
Arturas Dubickas, On the distance from a rational power to the nearest integer, Journal of Number Theory, Volume 117, Issue 1, March 2006, Pages 222-239.
Kurt Mahler, Arithmetische Eigenschaften der Lösungen einer Klasse von Funktionalgleichungen, Mathematische Annalen, Vol. 101 (1929), pp. 342-366, alternative link.
R. Schroeppel and R. W. Gosper, HACKMEM #122 (1972).
Eric Weisstein's World of Mathematics, Thue-Morse Constant.
Index entries for transcendental numbers

Cf. A000069, A001969, A010060, A058631, A215016, A247950.

A014571 := proc()
    local nlim,aold,a ;
    nlim := ilog2(10^Digits) ;
    aold := add( A010060(n)/2^n,n=0..nlim) ;
    a := 0.0 ;
    while abs(a-aold) > abs(a)/10^(Digits-3) do
        aold := a;
        nlim := nlim+200 ;
        a := add( A010060(n)/2^n,n=0..nlim) ;
    od:
    evalf(%/2) ;
end:
A014571() ; # R. J. Mathar, Mar 03 2008

digits = 105; t[0] = 0; t[n_?EvenQ] := t[n] = t[n/2]; t[n_?OddQ] := t[n] = 1-t[(n-1)/2]; FromDigits[{t /@ Range[digits*Log[10]/Log[2] // Ceiling], -1}, 2] // RealDigits[#, 10, digits]& // First (* Jean-François Alcover, Feb 20 2014 *)
1/2-1/4*Product[1-2^(-2^k), {k, 0, Infinity}] // N[#, 105]& // RealDigits // First (* Jean-François Alcover, May 15 2014, after Steven Finch *)
(* ThueMorse function needs $Version >= 10.2 *)
P = FromDigits[{ThueMorse /@ Range[0, 400], 0}, 2];
RealDigits[P, 10, 105][[1]] (* Jean-François Alcover, Jan 30 2020 *)

default(realprecision, 20080); x=0.0; m=67000; for (n=1, m-1, x=x+x; x=x+sum(k=0, length(binary(n))-1, bittest(n, k))%2); x=10*x/2^m; for (n=0, 20000, d=floor(x); x=(x-d)*10; write("b014571.txt", n, " ", d)); \\ Harry J. Smith, Apr 25 2009

1/2-prodinf(n=0,1-1.>>2^n)/4 \\ Charles R Greathouse IV, Jul 31 2012

Equals Sum_{k>=0} A010060(n)*2^(-(k+1)). [Corrected by Jianing Song, Oct 27 2018]
Equals Sum_{k>=1} 2^(-(A000069(k)+1)). - Jianing Song, Oct 27 2018
From Amiram Eldar, Nov 14 2020: (Start)
Equals 1/2 - (1/4) * A215016.
Equals 1/(3 - 1/A247950). (End)

Corrected and extended by R. J. Mathar, Mar 03 2008

A161579 Positions n such that A010060(n) = A010060(n+3).

Original entry on oeis.org

0, 1, 3, 4, 6, 8, 9, 11, 12, 13, 15, 16, 17, 19, 20, 22, 24, 25, 27, 28, 30, 32, 33, 35, 36, 38, 40, 41, 43, 44, 45, 47, 48, 49, 51, 52, 54, 56, 57, 59, 60, 61, 63, 64, 65, 67, 68, 70, 72, 73, 75, 76, 77, 79, 80, 81, 83, 84, 86, 88, 89, 91, 92, 94, 96, 97, 99, 100, 102, 104, 105, 107

Offset: 1

Vladimir Shevelev, Jun 14 2009

Or: union of A131323 with the sequence of terms of the form A131323(n)-2, and with the sequence of terms of the form A036554(n)-2.

Conjecture: In every sequence of numbers n such that A010060(n)=A010060(n+k), for fixed odd k, the odious (A000069) and evil (A001969) terms alternate. - Vladimir Shevelev, Jul 31 2009

G. C. Greubel, Table of n, a(n) for n = 1..10000
J.-P. Allouche, Thue, Combinatorics on words, and conjectures inspired by the Thue-Morse sequence, arXiv:1401.3727 [math.NT], 2014.
J.-P. Allouche, Thue, Combinatorics on words, and conjectures inspired by the Thue-Morse sequence, J. de Théorie des Nombres de Bordeaux, 27, no. 2 (2015), 375-388.
V. Shevelev, Equations of the form t(x+a)=t(x) and t(x+a)=1-t(x) for Thue-Morse sequence arXiv:0907.0880 [math.NT], 2009-2012. [_Vladimir Shevelev_, Jul 31 2009]

Cf. A131323, A036554, A010060, A121539, A079523, A081706, A161580.

tm[0] = 0; tm[n_?EvenQ] := tm[n] = tm[n/2]; tm[n_] := tm[n] = 1 - tm[(n-1)/2]; Reap[For[n = 0, n <= 200, n++, If[tm[n] == tm[n+3], Sow[n]]]][[2, 1]] (* Jean-François Alcover, Oct 24 2013 *)

is(n)=hammingweight(n)%2==hammingweight(n+3)%2 \\ Charles R Greathouse IV, Aug 20 2013

Equals {A001477} \ {A161580}.

More terms from R. J. Mathar, Aug 17 2009

A161580 Positions n such that A010060(n) + A010060(n+3) = 1.

Original entry on oeis.org

2, 5, 7, 10, 14, 18, 21, 23, 26, 29, 31, 34, 37, 39, 42, 46, 50, 53, 55, 58, 62, 66, 69, 71, 74, 78, 82, 85, 87, 90, 93, 95, 98, 101, 103, 106, 110, 114, 117, 119, 122, 125, 127, 130, 133, 135, 138, 142, 146, 149, 151, 154, 157, 159, 162, 165, 167, 170, 174, 178, 181, 183, 186

Offset: 1

Vladimir Shevelev, Jun 14 2009

nonn

Conjecture: In every sequence of numbers n such that A010060(n) + A010060(n+k) = 1, for fixed odd k, the odious (A000069) and evil (A001969) terms alternate. [From Vladimir Shevelev, Jul 31 2009]

G. C. Greubel, Table of n, a(n) for n = 1..10000
V. Shevelev,Equations of the form t(x+a)=t(x) and t(x+a)=1-t(x) for Thue-Morse sequence arXiv:0907.0880 [math.NT], 2009-2012. [_Vladimir Shevelev_, Jul 31 2009]

Cf. A131323 A036554, A010060, A121539, A079523, A081706, A161579

tm[0] = 0; tm[n_?EvenQ] := tm[n] = tm[n/2]; tm[n_] := tm[n] = 1 - tm[(n-1)/2]; Reap[For[n = 0, n <= 200, n++, If[tm[n] + tm[n+3] == 1, Sow[n]]]][[2, 1]] (* Jean-François Alcover, Oct 24 2013 *)

is(n)=hammingweight(n)%2+hammingweight(n+3)%2==1 \\ Charles R Greathouse IV, Mar 22 2013

A001477 \ A161579.

More terms from R. J. Mathar, Aug 17 2009

A161627 Positions n such that A010060(n)=A010060(n+4).

Original entry on oeis.org

4, 5, 6, 7, 20, 21, 22, 23, 28, 29, 30, 31, 36, 37, 38, 39, 52, 53, 54, 55, 68, 69, 70, 71, 84, 85, 86, 87, 92, 93, 94, 95, 100, 101, 102, 103, 116, 117, 118, 119, 124, 125, 126, 127, 132, 133, 134, 135, 148, 149, 150, 151, 156, 157, 158, 159, 164, 165, 166, 167, 180, 181, 182

Offset: 1

Vladimir Shevelev, Jun 15 2009

nonn

Or: union of the numbers of the form 4*A079523(n)+k, k=0, 1, 2, or 3.

Locates patterns of the form 1xxx1 or 0xxx0 in the Thue-Morse sequence.

Harvey P. Dale, Table of n, a(n) for n = 1..1000
J.-P. Allouche, Thue, Combinatorics on words, and conjectures inspired by the Thue-Morse sequence, arXiv preprint arXiv:1401.3727 [math.NT], 2014.
J.-P. Allouche, Thue, Combinatorics on words, and conjectures inspired by the Thue-Morse sequence, J. de Théorie des Nombres de Bordeaux, 27, no. 2 (2015), 375-388.
V. Shevelev, Equations of the form t(x+a)=t(x) and t(x+a)=1-t(x) for Thue-Morse sequence arXiv:0907.0880 [math.NT], 2009-2012. [From _Vladimir Shevelev_, Jul 31 2009]

Cf. A161579, A161580, A079523, A131323, A036554, A010060, A121539, A079523, A081706.

tm[0] = 0; tm[n_?EvenQ] := tm[n] = tm[n/2]; tm[n_] := tm[n] = 1 - tm[(n-1)/2]; Reap[For[n = 0, n <= 200, n++, If[tm[n] == tm[n+4], Sow[n]]]][[2, 1]] (* Jean-François Alcover, Oct 24 2013 *)
SequencePosition[ThueMorse[Range[200]],{x_,,,_,x_}][[All,1]] (* Requires Mathematica version 11 or later *) (* Harvey P. Dale, Apr 16 2017 *)

is(n)=hammingweight(n)%2==hammingweight(n+4)%2 \\ Charles R Greathouse IV, Aug 20 2013

Extended by R. J. Mathar, Aug 28 2009

A161639 Positions n such that A010060(n) = A010060(n+8).

Original entry on oeis.org

8, 9, 10, 11, 12, 13, 14, 15, 40, 41, 42, 43, 44, 45, 46, 47, 56, 57, 58, 59, 60, 61, 62, 63, 72, 73, 74, 75, 76, 77, 78, 79, 104, 105, 106, 107, 108, 109, 110, 111, 136, 137, 138, 139, 140, 141, 142, 143, 168, 169, 170, 171, 172, 173, 174, 175, 184, 185, 186, 187, 188, 189

Offset: 1

Vladimir Shevelev, Jun 15 2009

Locates correlations of the form 1xxxxxxx1 or 0xxxxxxx0 in the Thue-Morse sequence.
Or: union of numbers 8*A079523(n)+k, k=0, 1, 2, 3, 4, 5, 6, or 7.
Generalization: the numbers n such that A010060(n) = A010060(n+2^m) constitute the union of sequences {2^m*A079523(n)+k}, k=0,1,...,2^m-1.

G. C. Greubel, Table of n, a(n) for n = 1..10000
J.-P. Allouche, Thue, Combinatorics on words, and conjectures inspired by the Thue-Morse sequence, arXiv:1401.3727 [math.NT], 2014.
J.-P. Allouche, Thue, Combinatorics on words, and conjectures inspired by the Thue-Morse sequence, J. de Théorie des Nombres de Bordeaux, 27, no. 2 (2015), 375-388.
V. Shevelev, Equations of the form t(x+a)=t(x) and t(x+a)=1-t(x) for Thue-Morse sequence arXiv:0907.0880 [math.NT], 2009-2012. [_Vladimir Shevelev_, Jul 31 2009]

Cf. A161579, A161580, A161627, A131323, A036554, A010060, A121539, A079523, A081706

tm[0] = 0; tm[n_?EvenQ] := tm[n] = tm[n/2]; tm[n_] := tm[n] = 1 - tm[(n-1)/2]; Reap[For[n = 0, n <= 200, n++, If[tm[n] == tm[n+8], Sow[n]]]][[2, 1]] (* Jean-François Alcover, Oct 24 2013 *)
SequencePosition[ThueMorse[Range[0,200]],{x_,,,_,,,_,,x}][[All,1]]-1 (* Harvey P. Dale, Jul 23 2021 *)

is(n)=hammingweight(n)%2==hammingweight(n+8)%2 \\ Charles R Greathouse IV, Aug 20 2013

Duplicate of 174 removed by R. J. Mathar, Aug 28 2009

A161641 Positions n such that A010060(n) + A010060(n+4) = 1.

Original entry on oeis.org

0, 1, 2, 3, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 24, 25, 26, 27, 32, 33, 34, 35, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 88, 89, 90, 91, 96, 97, 98, 99, 104, 105, 106, 107, 108

Offset: 1

Vladimir Shevelev, Jun 15 2009

nonn

Also union of all numbers of the form A131323(n)-k, k=0, 1, 2, or 3.

G. C. Greubel, Table of n, a(n) for n = 1..10000

Cf. A161639, A161627, A161579, A161580, A079523, A131323, A036554, A010060, A121539, A079523, A081706.

tm[0] = 0; tm[n_?EvenQ] := tm[n] = tm[n/2]; tm[n_] := tm[n] = 1 - tm[(n - 1)/2]; Reap[For[n = 0, n <= 16000, n++, If[tm[n] + tm[n + 4] == 1, Sow[n]]]][[2, 1]] (* G. C. Greubel, Jan 01 2018 *)

is(n)=hammingweight(n)%2!=hammingweight(n+4)%2 \\ Charles R Greathouse IV, Aug 20 2013

A001477 \ A161627.

More terms from R. J. Mathar, Aug 17 2009

A161674 Positions n such that A010060(n) + A010060(n+2) = 1.

Original entry on oeis.org

0, 1, 4, 5, 6, 7, 8, 9, 12, 13, 16, 17, 20, 21, 22, 23, 24, 25, 28, 29, 30, 31, 32, 33, 36, 37, 38, 39, 40, 41, 44, 45, 48, 49, 52, 53, 54, 55, 56, 57, 60, 61, 64, 65, 68, 69, 70, 71, 72, 73, 76, 77, 80, 81, 84, 85, 86, 87, 88, 89, 92, 93, 94, 95, 96, 97, 100, 101, 102, 103, 104

Offset: 1

Vladimir Shevelev, Jun 16 2009

Locates patterns of the form 0x1 or 1x0 in the Thue-Morse sequence.
Complement to A081706. Also: union of sequences {2*A121539(n)+k}, k=0 or 1, generalized in A161673.
Also union of sequences {A079523(n)-k}, k=0 or 1. For a generalization see A161890. - Vladimir Shevelev, Jul 05 2009
The asymptotic density of this sequence is 2/3 (Rowland and Yassawi, 2015; Burns, 2016). - Amiram Eldar, Jan 30 2021

G. C. Greubel, Table of n, a(n) for n = 1..10000
Rob Burns, Asymptotic density of Motzkin numbers modulo small primes, arXiv:1611.04910 [math.NT], 2016.
Eric Rowland and Reem Yassawi, Automatic congruences for diagonals of rational functions, Journal de Théorie des Nombres de Bordeaux, Vol. 27, No. 1 (2015), pp. 245-288.

Cf. A161673, A161639, A161641, A161627, A161579, A161580, A161890, A121539, A131323, A036554, A010060, A079523, A081706.

tm[0] = 0; tm[n_?EvenQ] := tm[n] = tm[n/2]; tm[n_] := tm[n] = 1 - tm[(n - 1)/2]; Reap[For[n = 0, n <= 6000, n++, If[tm[n] + tm[n + 2] == 1, Sow[n]]]][[2, 1]] (* G. C. Greubel, Jan 05 2018 *)
Flatten[Position[Partition[ThueMorse[Range[0,120]],3,1],?(#[[1]]+#[[3]] == 1&),1,Heads->False]]-1 (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale, Oct 29 2019 *)

is(n)=hammingweight(n)%2!=hammingweight(n+2)%2 \\ Charles R Greathouse IV, Aug 20 2013

Extended by R. J. Mathar, Aug 28 2009

cp's OEIS Frontend

A026465 Length of n-th run of identical symbols in the Thue-Morse sequence A010060 (or A001285).

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A115384 Partial sums of Thue-Morse numbers A010060.

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A316828 Image of the Thue-Morse sequence A010060 under the morphism {1 -> 1,2; 0 -> 0,2}.

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A014571 Consider the Morse-Thue sequence (A010060) as defining a binary constant and convert it to decimal.

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A161579 Positions n such that A010060(n) = A010060(n+3).

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A161580 Positions n such that A010060(n) + A010060(n+3) = 1.

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A161627 Positions n such that A010060(n)=A010060(n+4).