login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A189706 Fixed point of the morphism 0->011, 1->001. 12
0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1

LINKS

Table of n, a(n) for n=1..122.

Index entries for 3-automatic sequences.

Index entries for sequences that are fixed points of mappings

FORMULA

a(3k-2)=0, a(3k-1)=1-a(k), a(3k)=1 for k>=1, a(0)=0.

EXAMPLE

0->011->011001001->...

MATHEMATICA

t = Nest[Flatten[# /. {0->{0, 1, 1}, 1->{0, 0, 1}}] &, {0}, 5] (* A189706 *)

f[n_] := t[[n]]

Flatten[Position[t, 0]] (* A189707 *)

Flatten[Position[t, 1]] (* A189708 *)

s[n_] := Sum[f[i], {i, 1, n}]; s[0] = 0;

Table[s[n], {n, 1, 120}] (* A189709 *)

PROG

(PARI) a(n) = n--; my(ret=0); while([n, r]=divrem(n, 3); r==1, ret++); (ret+r>>1)%2; \\ Kevin Ryde, Jun 02 2021

CROSSREFS

Cf. A189628, A189707, A189708, A189709.

Cf. A321090, A321091, A321093, A321095, A321097.

Sequence in context: A140591 A189476 A288752 * A188321 A257628 A203568

Adjacent sequences:  A189703 A189704 A189705 * A189707 A189708 A189709

KEYWORD

nonn

AUTHOR

Clark Kimberling, Apr 25 2011

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 27 18:27 EDT 2021. Contains 346308 sequences. (Running on oeis4.)