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 1-6 of 6 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 *)

A140427 Arises in relating doubly-even error-correcting codes, graphs and irreducible representations of N-extended supersymmetry.

Original entry on oeis.org

0, 0, 0, 0, 1, 1, 2, 3, 4, 4, 4, 4, 5, 5, 6, 7, 8, 8, 8, 8, 9, 9, 10, 11, 12, 12, 12, 12, 13, 13, 14, 15, 16, 16, 16, 16, 17, 17, 18, 19, 20, 20, 20, 20, 21, 21, 22, 23, 24, 24, 24, 24, 25, 25, 26, 27, 28, 28, 28, 28, 29, 29, 30
Offset: 0

Views

Author

Jonathan Vos Post, Jun 18 2008

Keywords

Comments

Conjecture: essentially partial sums of A169675 (verified for n <= 10000). - Sean A. Irvine, Jul 19 2022

Programs

  • Maple
    A140427 := proc(n) local l: l:=[0, 0, 0, 0, 1, 1, 2, 3]: if(n<=7)then return l[n+1]:else return l[(n mod 8) + 1] + 4*floor(n/8): fi: end:
    seq(A140427(n),n=0..62); # Nathaniel Johnston, Apr 26 2011
  • Mathematica
    a[n_] := Module[{L = {0, 0, 0, 0, 1, 1, 2, 3}}, If[n <= 7, L[[n + 1]], L[[Mod[n, 8] + 1]] + 4*Floor[n/8]]];
    Table[a[n], {n, 0, 62}] (* Jean-François Alcover, Nov 28 2017, from Maple *)

Formula

a(n) = 0 for 0 <= n < 4, a(n) = floor(((n-4)^2)/4)+1 for n = 4, 5, 6, 7, and a(n) = a(n-8) + 4 for n>7.
G.f.: x^4*(x^4+x^3+x^2+1) / ((x-1)^2*(x+1)*(x^2+1)*(x^4+1)). - Colin Barker, May 04 2013

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, ...
Showing 1-6 of 6 results.