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 1-2 of 2 results.

A176461 Decimal expansion of sqrt(105).

Original entry on oeis.org

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

Views

Author

Klaus Brockhaus, Apr 20 2010

Keywords

Comments

Continued fraction expansion of sqrt(105) is A040094.

Examples

			sqrt(105) = 10.24695076595959838322...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[Sqrt[105],10,120][[1]] (* Harvey P. Dale, Aug 03 2016 *)

A041189 Denominators of continued fraction convergents to sqrt(105).

Original entry on oeis.org

1, 4, 81, 328, 6641, 26892, 544481, 2204816, 44640801, 180768020, 3660001201, 14820772824, 300075457681, 1215122603548, 24602527528641, 99625232718112, 2017107181890881, 8168053960281636, 165378186387523601, 669680799510376040
Offset: 0

Views

Author

Keywords

Crossrefs

Cf. A040094, A041188 (numerators), A176461.

Programs

  • Magma
    I:=[1,4,81,328]; [n le 4 select I[n] else 82*Self(n-2)-Self(n-4): n in [1..30]]; // Vincenzo Librandi, Dec 12 2013
  • Mathematica
    Denominator/@Convergents[Sqrt[105],30]  (* Harvey P. Dale, Apr 02 2011 *)
    CoefficientList[Series[(1 + 4 x - x^2)/(1 - 82 x^2 + x^4), {x, 0, 30}], x] (* Vincenzo Librandi, Dec 12 2013*)

Formula

G.f.: (1 + 4*x - x^2)/(1 - 82*x^2 + x^4). - Vincenzo Librandi, Dec 12 2013
a(n) = 82*a(n-2) - a(n-4). - Vincenzo Librandi, Dec 12 2013

Extensions

a(19) from Vincenzo Librandi, Dec 12 2013
Showing 1-2 of 2 results.