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 1-5 of 5 results.

A248291 Egyptian fraction representation of sqrt(67) (A010519) using a greedy function.

Original entry on oeis.org

8, 6, 54, 5968, 37928283, 14186508539132240, 215574431124169048574472920051105, 619113864242566215185357331731644567622871533734575552668037746157, 1026704635586993757466869990798845550899476775104786232072062922961543188349830119350020024351935013557637621452049626418228548257237
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[ 67]]

A010147 Continued fraction for sqrt(67).

Original entry on oeis.org

8, 5, 2, 1, 1, 7, 1, 1, 2, 5, 16, 5, 2, 1, 1, 7, 1, 1, 2, 5, 16, 5, 2, 1, 1, 7, 1, 1, 2, 5, 16, 5, 2, 1, 1, 7, 1, 1, 2, 5, 16, 5, 2, 1, 1, 7, 1, 1, 2, 5, 16, 5, 2, 1, 1, 7, 1, 1, 2, 5, 16, 5, 2, 1, 1, 7, 1, 1, 2, 5, 16, 5, 2, 1, 1, 7, 1, 1
Offset: 0

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Author

Keywords

Examples

			8.185352771872449969953703724... = 8 + 1/(5 + 1/(2 + 1/(1 + 1/(1 + ...)))). - _Harry J. Smith_, Jun 08 2009
		

Crossrefs

Cf. A010519 Decimal expansion. - Harry J. Smith, Jun 08 2009

Programs

  • Mathematica
    ContinuedFraction[Sqrt[67],300] (* Vladimir Joseph Stephan Orlovsky, Mar 08 2011 *)
    PadRight[{8},120,{16,5,2,1,1,7,1,1,2,5}] (* Harvey P. Dale, Jun 02 2025 *)
  • PARI
    { allocatemem(932245000); default(realprecision, 21000); x=contfrac(sqrt(67)); for (n=0, 20000, write("b010147.txt", n, " ", x[n+1])); } \\ Harry J. Smith, Jun 08 2009

A176443 Decimal expansion of sqrt(469).

Original entry on oeis.org

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

Views

Author

Klaus Brockhaus, Apr 19 2010

Keywords

Comments

Continued fraction expansion of sqrt(469) is A040447.

Examples

			sqrt(469) = 21.65640782770771520178...
		

Crossrefs

Cf. A010465 (decimal expansion of sqrt(7)), A010519 (decimal expansion of sqrt(67)), A176442 (decimal expansion of (21+sqrt(469))/6), A040447.

Programs

  • Mathematica
    RealDigits[Sqrt[469],10,120][[1]] (* Harvey P. Dale, May 28 2025 *)

A041116 Numerators of continued fraction convergents to sqrt(67).

Original entry on oeis.org

8, 41, 90, 131, 221, 1678, 1899, 3577, 9053, 48842, 790525, 4001467, 8793459, 12794926, 21588385, 163913621, 185502006, 349415627, 884333260, 4771081927, 77221644092, 390879302387, 858980248866, 1249859551253, 2108839800119, 16011738152086, 18120577952205
Offset: 0

Views

Author

Keywords

Crossrefs

Programs

  • Mathematica
    Numerator[Convergents[Sqrt[67], 30]] (* Vincenzo Librandi, Oct 29 2013 *)

Formula

G.f.: -(x^19 -8*x^18 +41*x^17 -90*x^16 +131*x^15 -221*x^14 +1678*x^13 -1899*x^12 +3577*x^11 -9053*x^10 -48842*x^9 -9053*x^8 -3577*x^7 -1899*x^6 -1678*x^5 -221*x^4 -131*x^3 -90*x^2 -41*x -8) / (x^20 -97684*x^10 +1). - Colin Barker, Nov 10 2013

Extensions

More terms from Colin Barker, Nov 10 2013

A041117 Denominators of continued fraction convergents to sqrt(67).

Original entry on oeis.org

1, 5, 11, 16, 27, 205, 232, 437, 1106, 5967, 96578, 488857, 1074292, 1563149, 2637441, 20025236, 22662677, 42687913, 108038503, 582880428, 9434125351, 47753507183, 104941139717, 152694646900, 257635786617, 1956145153219, 2213780939836, 4169926093055
Offset: 0

Views

Author

Keywords

Crossrefs

Programs

  • Magma
    I:=[1, 5, 11, 16, 27, 205, 232, 437, 1106, 5967, 96578, 488857, 1074292, 1563149, 2637441, 20025236, 22662677, 42687913, 108038503, 582880428]; [n le 20 select I[n] else 97684*Self(n-10)-Self(n-20): n in [1..40]]; // Vincenzo Librandi, Dec 11 2013
  • Mathematica
    Table[Denominator[FromContinuedFraction[ContinuedFraction[Sqrt[67],n]]],{n,1,50}] (* Vladimir Joseph Stephan Orlovsky, Jun 26 2011 *)
    Denominator[Convergents[Sqrt[67], 30]] (* Harvey P. Dale, Oct 03 2012 *)
    CoefficientList[Series[-(x^18 - 5 x^17 + 11 x^16 - 16 x^15 + 27 x^14 - 205 x^13 + 232 x^12 - 437 x^11 + 1106 x^10 - 5967 x^9 - 1106 x^8 - 437 x^7 - 232 x^6 - 205 x^5 - 27 x^4 - 16 x^3 - 11 x^2 - 5 x - 1)/(x^20 - 97684 x^10 + 1), {x, 0, 30}], x] (* Vincenzo Librandi, Dec 11 2013 *)

Formula

G.f.: -(x^18 -5*x^17 +11*x^16 -16*x^15 +27*x^14 -205*x^13 +232*x^12 -437*x^11 +1106*x^10 -5967*x^9 -1106*x^8 -437*x^7 -232*x^6 -205*x^5 -27*x^4 -16*x^3 -11*x^2 -5*x -1) / (x^20 -97684*x^10 +1). - Colin Barker, Nov 13 2013
a(n) = 97684*a(n-10) - a(n-20). - Vincenzo Librandi, Dec 11 2013

Extensions

More terms from Colin Barker, Nov 13 2013
Showing 1-5 of 5 results.