cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-3 of 3 results.

A106795 Fixed point of the morphism 1 -> 1,1,1,1,1,1,2,2,2,3; 2 -> 2,2,3,1,1,1,1; 3 -> 3,1,1,1,2,2, starting with a(0) = 1.

Original entry on oeis.org

1, 1, 1, 1, 1, 1, 2, 2, 2, 3, 1, 1, 1, 1, 1, 1, 2, 2, 2, 3, 1, 1, 1, 1, 1, 1, 2, 2, 2, 3, 1, 1, 1, 1, 1, 1, 2, 2, 2, 3, 1, 1, 1, 1, 1, 1, 2, 2, 2, 3, 1, 1, 1, 1, 1, 1, 2, 2, 2, 3, 2, 2, 3, 1, 1, 1, 1, 2, 2, 3, 1, 1, 1, 1, 2, 2, 3, 1, 1, 1, 1, 3, 1, 1, 1, 2, 2
Offset: 0

Views

Author

Roger L. Bagula, May 17 2005

Keywords

Comments

3-symbol substitution for the characteristic polynomial: x^3 + 9*x^2 - 3*x - 1.

Examples

			The first few steps of the substitution are:
Start: 1
Maps:
  1 --> 1 1 1 1 1 1 2 2 2 3
  2 --> 2 2 3 1 1 1 1
  3 --> 3 1 1 1 2 2
-------------
0:   (#=1)
  1
1:   (#=10)
  1111112223
		

Crossrefs

Programs

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

Extensions

Edited by G. C. Greubel, Apr 03 2022

A106796 Fixed point of the morphism 1 -> 1,1,2; 2 -> 3; 3 -> 1,4; 4 -> 1, starting with a(0) = 1.

Original entry on oeis.org

1, 1, 2, 1, 1, 2, 3, 1, 1, 2, 1, 1, 2, 3, 1, 4, 1, 1, 2, 1, 1, 2, 3, 1, 1, 2, 1, 1, 2, 3, 1, 4, 1, 1, 2, 1, 1, 1, 2, 1, 1, 2, 3, 1, 1, 2, 1, 1, 2, 3, 1, 4, 1, 1, 2, 1, 1, 2, 3, 1, 1, 2, 1, 1, 2, 3, 1, 4, 1, 1, 2, 1, 1, 1, 2, 1, 1, 2, 3, 1, 1, 2, 1, 1, 2, 1, 1, 2, 3, 1, 1, 2, 1, 1, 2, 3, 1, 4, 1, 1, 2, 1, 1, 2, 3
Offset: 0

Views

Author

Roger L. Bagula, May 17 2005

Keywords

Comments

4-symbol substitution for the Pisot characteristic polynomial: x^4 - 2*x^2 - x - 1.

Examples

			The first few steps of the substitution are:
Start: 1
Maps:
  1 --> 1 1 2
  2 --> 3
  3 --> 1 4
  4 --> 1
-------------
0:   (#=1)
  1
1:   (#=3)
  112
2:   (#=7)
  1121123
3:   (#=16)
  1121123112112314
4:   (#=36)
  112112311211231411211231121123141121
5:   (#=82)
  1121123112112314112112311211231411211121123112112314112112311211231411211121123112
		

Crossrefs

Programs

  • Mathematica
    s[1]= {1, 1, 2}; s[2]= {3}; s[3]= {1, 4}; s[4]= {1}; t[b_]:= Flatten[s /@ b];
    a[0]= {1}; a[1]= t[p[0]]; a[n_]:= t[a[n-1]];
    a[10]

Extensions

Edited by G. C. Greubel, Apr 03 2022

A106798 Fixed point of the morphism 1 -> 3; 2 -> 1,2,2; 3 -> 1,2, starting with a(0) = 1.

Original entry on oeis.org

1, 2, 3, 1, 2, 2, 1, 2, 2, 3, 1, 2, 2, 1, 2, 3, 1, 2, 2, 1, 2, 2, 3, 1, 2, 2, 1, 2, 2, 1, 2, 3, 1, 2, 2, 1, 2, 2, 3, 1, 2, 2, 1, 2, 2, 3, 1, 2, 2, 1, 2, 3, 1, 2, 2, 1, 2, 2, 3, 1, 2, 2, 1, 2, 2, 1, 2, 3, 1, 2, 2, 1, 2, 2, 3, 1, 2, 2, 1, 2, 3, 1, 2, 2, 1, 2, 2, 3, 1, 2, 2, 1, 2, 2, 1, 2, 3, 1, 2, 2, 1, 2, 2, 3, 1
Offset: 0

Views

Author

Roger L. Bagula, May 17 2005

Keywords

Comments

3-symbol substitution for the characteristic polynomial: x^3 - 2*x^2 - x + 1.

Examples

			The first few steps of the substitution are:
Start: 1
Maps:
  1 --> 3
  2 --> 1 2 2
  3 --> 1 2
-------------
a(n) = p(2*n)
-------------
0:   (#=1) (p(0))
  1
1:   (#=2) (p(2))
  12
2:   (#=9) (p(4))
  123122122
3:   (#=45) (p(6))
  123122122312212312212231221221231221223122122
		

Crossrefs

Programs

  • Mathematica
    s[1]= {3}; s[2]= {1,2,2}; s[3]= {1,2}; t[b_]:= Flatten[s /@ b];
    p[0]= {1}; p[1]= t[p[0]]; p[n_]:= t[p[n-1]];
    a[n_]:= p[2*n];
    a[4]

Formula

a(n) = p(2*n), where p(n) maps the fixed point morphism 1 -> 3; 2 -> 1,2,2; 3 -> 1,2, starting with p(0) = 1.

Extensions

Edited by G. C. Greubel, Apr 03 2022
Showing 1-3 of 3 results.