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.

A248314 Egyptian fraction representation of sqrt(91) (A010542) using a greedy function.

Original entry on oeis.org

9, 2, 26, 1075, 4112692, 27635607215221, 849264815973068493208894568, 4841632147722920600382393247090367280521902842548984840, 266615765339465306160951850397944334901944400721855522651965673953142506552009472018442954194685982876108261727
Offset: 0

Views

Author

Robert G. Wilson v, Oct 04 2014

Keywords

Crossrefs

Egyptian fraction representations of the square roots: A006487, A224231, A248235-A248322.
Egyptian fraction representations of the cube roots: A129702, A132480-A132574.

Programs

  • Mathematica
    Egyptian[nbr_] := Block[{lst = {IntegerPart[nbr]}, cons = N[ FractionalPart[ nbr], 2^20], denom, iter = 8}, While[ iter > 0, denom = Ceiling[ 1/cons]; AppendTo[ lst, denom]; cons -= 1/denom; iter--]; lst]; Egyptian[ Sqrt[ 91]]

A010162 Continued fraction for sqrt(91).

Original entry on oeis.org

9, 1, 1, 5, 1, 5, 1, 1, 18, 1, 1, 5, 1, 5, 1, 1, 18, 1, 1, 5, 1, 5, 1, 1, 18, 1, 1, 5, 1, 5, 1, 1, 18, 1, 1, 5, 1, 5, 1, 1, 18, 1, 1, 5, 1, 5, 1, 1, 18, 1, 1, 5, 1, 5, 1, 1, 18, 1, 1, 5, 1, 5, 1, 1, 18, 1, 1, 5, 1, 5, 1, 1, 18, 1, 1, 5, 1, 5
Offset: 0

Views

Author

Keywords

Examples

			9.539392014169456491526215860... = 9 + 1/(1 + 1/(1 + 1/(5 + 1/(1 + ...)))). - _Harry J. Smith_, Jun 11 2009
		

Crossrefs

Cf. A010542 Decimal expansion. - Harry J. Smith, Jun 11 2009

Programs

  • Mathematica
    ContinuedFraction[Sqrt[91],300] (* Vladimir Joseph Stephan Orlovsky, Mar 10 2011 *)
  • PARI
    { allocatemem(932245000); default(realprecision, 18000); x=contfrac(sqrt(91)); for (n=0, 20000, write("b010162.txt", n, " ", x[n+1])); } \\ Harry J. Smith, Jun 11 2009

A041162 Numerators of continued fraction convergents to sqrt(91).

Original entry on oeis.org

9, 10, 19, 105, 124, 725, 849, 1574, 29181, 30755, 59936, 330435, 390371, 2282290, 2672661, 4954951, 91861779, 96816730, 188678509, 1040209275, 1228887784, 7184648195, 8413535979, 15598184174, 289180851111, 304779035285, 593959886396, 3274578467265
Offset: 0

Views

Author

Keywords

Crossrefs

Programs

  • Mathematica
    Numerator[Convergents[Sqrt[91], 30]] (* Vincenzo Librandi, Oct 29 2013 *)

Formula

G.f.: -(x^15 -9*x^14 +10*x^13 -19*x^12 +105*x^11 -124*x^10 +725*x^9 -849*x^8 -1574*x^7 -849*x^6 -725*x^5 -124*x^4 -105*x^3 -19*x^2 -10*x -9) / (x^16 -3148*x^8 +1). - Colin Barker, Nov 05 2013

Extensions

More terms from Colin Barker, Nov 05 2013

A041163 Denominators of continued fraction convergents to sqrt(91).

Original entry on oeis.org

1, 1, 2, 11, 13, 76, 89, 165, 3059, 3224, 6283, 34639, 40922, 239249, 280171, 519420, 9629731, 10149151, 19778882, 109043561, 128822443, 753155776, 881978219, 1635133995, 30314390129, 31949524124, 62263914253, 343269095389, 405533009642, 2370934143599
Offset: 0

Views

Author

Keywords

Crossrefs

Programs

  • Magma
    I:=[1, 1, 2, 11, 13, 76, 89, 165, 3059, 3224, 6283, 34639, 40922, 239249, 280171, 519420]; [n le 16 select I[n] else 3148*Self(n-8)-Self(n-16): n in [1..40]]; // Vincenzo Librandi, Dec 12 2013
  • Mathematica
    Denominator[Convergents[Sqrt[91], 30]] (* Bruno Berselli, Nov 14 2013 *)
    CoefficientList[Series[-(x^14 - x^13 + 2 x^12 - 11 x^11 + 13 x^10 - 76 x^9 + 89 x^8 - 165 x^7 - 89 x^6 - 76 x^5 - 13 x^4 - 11 x^3 - 2 x^2 - x - 1)/(x^16 - 3148 x^8 + 1), {x, 0, 30}], x] (* Vincenzo Librandi, Dec 12 2013 *)

Formula

G.f.: -(x^14 -x^13 +2*x^12 -11*x^11 +13*x^10 -76*x^9 +89*x^8 -165*x^7 -89*x^6 -76*x^5 -13*x^4 -11*x^3 -2*x^2 -x -1) / (x^16 -3148*x^8 +1). - Colin Barker, Nov 14 2013
a(n) = 3148*a(n-8) - a(n-16). - Vincenzo Librandi, Dec 12 2013

Extensions

More terms from Colin Barker, Nov 14 2013
Showing 1-4 of 4 results.