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 1-4 of 4 results.

A010464 Decimal expansion of square root of 6.

Original entry on oeis.org

2, 4, 4, 9, 4, 8, 9, 7, 4, 2, 7, 8, 3, 1, 7, 8, 0, 9, 8, 1, 9, 7, 2, 8, 4, 0, 7, 4, 7, 0, 5, 8, 9, 1, 3, 9, 1, 9, 6, 5, 9, 4, 7, 4, 8, 0, 6, 5, 6, 6, 7, 0, 1, 2, 8, 4, 3, 2, 6, 9, 2, 5, 6, 7, 2, 5, 0, 9, 6, 0, 3, 7, 7, 4, 5, 7, 3, 1, 5, 0, 2, 6, 5, 3, 9, 8, 5, 9, 4, 3, 3, 1, 0, 4, 6, 4, 0, 2, 3
Offset: 1

Views

Author

Keywords

Comments

Continued fraction expansion is 2 followed by {2, 4} repeated. - Harry J. Smith, Jun 05 2009
Ratio t*o/c^2 where t, o and c are respectively the edge lengths of a tetrahedron, an octahedron and a cube whose total surface areas are the same. See CNRS links. - Michel Marcus, Mar 03 2022 and Apr 21 2016
Diameter of a sphere whose surface area equals 6*Pi. More generally, the square root of x is also the diameter of a sphere whose surface area equals x*Pi. - Omar E. Pol, Aug 29 2024

Examples

			2.449489742783178098197284074705891391965947480656670128432692567250960...
Sqrt(6) = sqrt(1+i*sqrt(3)) + sqrt(1-i*sqrt(3)), where i=sqrt(-1). - _Bruno Berselli_, Nov 20 2012
		

Crossrefs

Cf. A002193 (sqrt(2)), A002194 (sqrt(3)).
Cf. A040003 (continued fraction).

Programs

Formula

Equals A002193*A002194. - Michel Marcus, Apr 21 2016

A382713 Simple continued fraction expansion of sqrt(3/2).

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane, Apr 08 2025

Keywords

Crossrefs

Essentially the same as A106469, A040003, A010694.

Programs

  • Maple
    with(numtheory); cfrac (sqrt(3/2, 70, 'quotients');
  • Mathematica
    PadRight[{1}, 100, {2, 4}] (* Paolo Xausa, Apr 14 2025 *)
  • Python
    def A382713(n): return 1<<1+(n&1) if n else 1 # Chai Wah Wu, Apr 09 2025

A004564 Expansion of sqrt(6) in base 5.

Original entry on oeis.org

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

Views

Author

Keywords

Examples

			In base 5: sqrt(11) = 2.21104311431133134121411...
		

Crossrefs

Programs

  • Magma
    d:= 6; m:=5; Prune(Reverse(IntegerToSequence(Isqrt(d*m^100), m))); // G. C. Greubel, Mar 26 2018
  • Mathematica
    RealDigits[Sqrt[6], 5, 100][[1]] (* Alonso del Arte, Aug 27 2012 *)

Extensions

Updated by Alois P. Heinz at the suggestion of Kevin Ryde, Feb 19 2012

A064851 Period of continued fraction for sqrt(6)*n.

Original entry on oeis.org

2, 2, 6, 4, 2, 6, 6, 8, 2, 2, 4, 12, 16, 6, 12, 12, 22, 2, 18, 2, 24, 4, 20, 20, 18, 12, 10, 8, 22, 8, 26, 32, 4, 14, 8, 8, 40, 10, 40, 4, 34, 16, 38, 8, 8, 16, 40, 44, 2, 14, 10, 24, 50, 10, 12, 4, 18, 22, 22, 8, 56, 26, 20, 60, 32, 4, 58, 24, 60, 4, 68, 20, 34, 40, 58, 24, 28, 44
Offset: 1

Views

Author

R. K. Guy, Oct 26 2001

Keywords

Examples

			A040003 (cfrac for n=1) has period length 2, so a(1)=2. A040019 (cfrac for n=2) has period length 2, so a(2)=2. A010140 (cfrac for n=3) has period length 6, so a(3)=6. - _R. J. Mathar_, Feb 10 2016
		
Showing 1-4 of 4 results.