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 1-8 of 8 results.

A169671 Lexicographically earliest de Bruijn sequence for n = 6 and k = 2.

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 0
Offset: 0

Views

Author

N. J. A. Sloane, Apr 11 2010

Keywords

Examples

			Periodic with period 64, the period being:
0000001000011000101000111001001011001101001111010101110110111111.
		

Crossrefs

See A058342 for another version.

A169673 Lexicographically earliest de Bruijn sequence for n = 7 and k = 2.

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 1, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1
Offset: 0

Views

Author

N. J. A. Sloane, Apr 11 2010

Keywords

Examples

			Periodic with period 128, the period being:
00000001000001100001010000111000100100010110001101000111100100110\
010101001011100110110011101001111101010110101111011011101111111
		

Crossrefs

A169674 Lexicographically earliest de Bruijn sequence for n = 8 and k = 2.

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 0, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 1, 0
Offset: 0

Views

Author

N. J. A. Sloane, Apr 11 2010

Keywords

Examples

			Periodic with period 256, the period being:
0000000010000001100000101000001110000100100001011000011010000111100010\
0010011000101010001011100011001000110110001110100011111001001010010011\
1001010110010110100101111001100110101001101110011101100111101001111110\
1010101110101101101011111011011110111011111111
		

Crossrefs

A169672 Lexicographically earliest de Bruijn sequence for n = 5 and k = 2.

Original entry on oeis.org

0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 0, 0, 0
Offset: 0

Views

Author

N. J. A. Sloane, Apr 11 2010

Keywords

Examples

			Periodic with period 32, the period being: 00000100011001010011101011011111.
		

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1},{0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 1, 1, 1},99] (* Ray Chandler, Aug 26 2015 *)

A169675 Lexicographically earliest de Bruijn sequence for n = 3 and k = 2.

Original entry on oeis.org

0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 0
Offset: 0

Views

Author

N. J. A. Sloane, Apr 11 2010

Keywords

Comments

The lexicographically earliest de Bruijn sequence for n = 2 and k = 2 is 0011 repeated (see A021913).

Examples

			Periodic with period 8, the period being 00010111.
		

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{0, 0, 0, 0, 0, 0, 0, 1},{0, 0, 0, 1, 0, 1, 1, 1},99] (* Ray Chandler, Aug 25 2015 *)
    PadRight[{},120,{0,0,0,1,0,1,1,1}] (* Harvey P. Dale, Aug 01 2024 *)

A169676 Lexicographically earliest de Bruijn sequence for n = 2 and k = 3.

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Apr 11 2010

Keywords

Examples

			Periodic with period 9, the period being 001021122.
		

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{0, 0, 0, 0, 0, 0, 0, 0, 1},{0, 0, 1, 0, 2, 1, 1, 2, 2},99] (* Ray Chandler, Aug 26 2015 *)

Extensions

If someone would like to help, I would like to get analogous entries for k = 3 and n = 3,4,5,6; k = 4 and n = 2,3,4,5,6; k = 5 and n = 2,3,4,5,6; and n = 2 and k = 6,7,8,9, ...

A308831 Start with generation 0, which is the empty sequence. For generation N>=1, extend the existing sequence into a non-cyclic ternary de Bruijn sequence of order N. If more than one extension is possible, choose the lexicographically earliest.

Original entry on oeis.org

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

Views

Author

A. D. Skovgaard, Jun 27 2019

Keywords

Comments

If using a binary alphabet instead, it would not be possible to extend the sequence infinitely as a de Bruijn sequence (order 3 needs an extra term: 01100010111). - A. D. Skovgaard, Apr 19 2020

Examples

			Generation 1:
[012] (All ternary sequences of length 1 now appear. With 3! = 6 solutions, the lexicographically earliest is chosen.)
Generation 2:
[0120022110] (The sequence is extended from the previous generation, now including all ternary sequences of length 2.)
The process continues.
		

Crossrefs

Cf. A080679 (binary equivalent), A166315, A169676.

A144569 A de Bruijn sequence B(4,3) found by Ted Bell.

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Apr 09 2010, based on a communication from David Paterson (David.Paterson(AT)csiro.au)

Keywords

Examples

			Period 64: 0001110100202221211220030333232233131133013203210310231201230213
		

Crossrefs

A135472 gives an example of a B(9,2).
Showing 1-8 of 8 results.