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!)
A106645 A four-symbol substitution with characteristic polynomial x^4-x-1. 0
2, 4, 1, 2, 4, 1, 3, 1, 2, 4, 1, 2, 4, 1, 3, 1, 3, 4, 3, 1, 3, 1, 2, 4, 1, 2, 4, 1, 3, 1, 2, 4, 1, 2, 4, 1, 3, 1, 3, 4, 3, 1, 3, 1, 3, 4, 3, 2, 4, 3, 4, 3, 1, 3, 1, 3, 4, 3, 1, 3, 1, 2, 4, 1, 2, 4, 1, 3, 1, 2, 4, 1, 2, 4, 1, 3, 1, 3, 4, 3, 1, 3, 1, 2, 4, 1, 2, 4, 1, 3, 1, 2, 4, 1, 2, 4, 1, 3, 1, 3, 4, 3, 1, 3, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

A minimal Pisot like substitution, but in 4 symbols.

LINKS

Table of n, a(n) for n=0..104.

FORMULA

1->{2, 4}, 2->{3, 4}, 3->{1}, 4->{3}

MATHEMATICA

s[1] = {2, 4}; s[2] = {3, 4}; s[3] = {1}; s[4] = {3}; t[a_] := Flatten[s /@ a]; p[0] = {1}; p[1] = t[p[0]]; p[n_] := t[p[n - 1]] aa = p[16]

CROSSREFS

Sequence in context: A124911 A132954 A069705 * A115314 A062039 A035492

Adjacent sequences:  A106642 A106643 A106644 * A106646 A106647 A106648

KEYWORD

nonn,uned

AUTHOR

Roger L. Bagula, May 12 2005

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 March 30 10:31 EDT 2020. Contains 333125 sequences. (Running on oeis4.)