login
This site is supported by donations to The OEIS Foundation.
Logo

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A138967 Infinite Fibonacci word on the alphabet (1,2,3,4). 1
1, 2, 3, 1, 4, 1, 2, 3, 1, 2, 3, 1, 4, 1, 2, 3, 1, 4, 1, 2, 3, 1, 2, 3, 1, 4, 1, 2, 3, 1, 2, 3, 1, 4, 1, 2, 3, 1, 4, 1, 2, 3, 1, 2, 3, 1, 4, 1, 2, 3, 1, 4, 1, 2, 3, 1, 2, 3, 1, 4, 1, 2, 3, 1, 2, 3, 1, 4, 1, 2, 3, 1, 4, 1, 2, 3, 1, 2, 3, 1, 4, 1, 2, 3, 1, 2, 3, 1, 4, 1, 2, 3, 1, 4, 1, 2, 3, 1, 2, 3, 1, 4, 1, 2, 3 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

a(n)=3 for n=3,8,21,55,..., F(2k), k>1.

a(n)=4 for n=5,13,34,89,..., F(2k+1), k>1.

Start with the infinite Fibonacci word A003849, which is

0 1 0 0 1 0 1 0 0 1 0 0 1 0 1 0 0 1 0 ... and replace

each 0 by 1,2,3 and each 1 by 1,4; the result is A138967.

FORMULA

Let A(n)=floor(n*tau), B(n)=n+floor(n*tau); i.e., A and B are the lower and upper Wythoff sequences, A=A000201, B=001950. a(n)=1 if n=A(A(k)) for some k; a(n)=2 if n=B(A(k)) for some k; a(n)=3 if n=A(B(k)) for some k; a(n)=4 if n=B(B(k)) for some k.

CROSSREFS

Cf. A000201, A001950, A003849, A101864.

Sequence in context: A097744 A055445 A135560 * A035612 A199539 A089555

Adjacent sequences:  A138964 A138965 A138966 * A138968 A138969 A138970

KEYWORD

nonn

AUTHOR

Clark Kimberling (ck6(AT)evansville.edu), Apr 04 2008

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
Recent Additions | More pages | Superseeker | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified February 16 20:28 EST 2012. Contains 205962 sequences.