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.

A248294 Egyptian fraction representation of sqrt(70) (A010522) using a greedy function.

Original entry on oeis.org

8, 3, 31, 992, 1245369, 3302336350417, 47523810173595463077699706, 15227181289661678179456803859437449044352739723867580, 290150350103448613285887398334236111049315440797539935407545942151460489216853681370927408862165807652692
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[ 70]]

A010149 Continued fraction for sqrt(70).

Original entry on oeis.org

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

Views

Author

Keywords

Examples

			8.366600265340755479781720257... = 8 + 1/(2 + 1/(1 + 1/(2 + 1/(1 + ...)))). - _Harry J. Smith_, Jun 08 2009
		

Crossrefs

Cf. A010522 Decimal expansion. - Harry J. Smith, Jun 08 2009

Programs

  • Mathematica
    ContinuedFraction[Sqrt[70],300] (* Vladimir Joseph Stephan Orlovsky, Mar 08 2011 *)
    PadRight[{8},120,{16,2,1,2,1,2}] (* Harvey P. Dale, Mar 25 2020 *)
  • PARI
    { allocatemem(932245000); default(realprecision, 19000); x=contfrac(sqrt(70)); for (n=0, 20000, write("b010149.txt", n, " ", x[n+1])); } \\ Harry J. Smith, Jun 08 2009

A041122 Numerators of continued fraction convergents to sqrt(70).

Original entry on oeis.org

8, 17, 25, 67, 92, 251, 4108, 8467, 12575, 33617, 46192, 126001, 2062208, 4250417, 6312625, 16875667, 23188292, 63252251, 1035224308, 2133700867, 3168925175, 8471551217, 11640476392, 31752504001
Offset: 0

Views

Author

Keywords

Crossrefs

Programs

  • Mathematica
    Numerator[Convergents[Sqrt[70], 30]] (* Vincenzo Librandi, Oct 26 2013 *)
    LinearRecurrence[{0,0,0,0,0,502,0,0,0,0,0,-1},{8,17,25,67,92,251,4108,8467,12575,33617,46192,126001},30] (* Harvey P. Dale, Dec 12 2024 *)

Formula

a(n) = 502*a(n-6)-a(n-12). G.f.: -(x+1)*(x^10-9*x^9+26*x^8-51*x^7+118*x^6-210*x^5-41*x^4-51*x^3-16*x^2-9*x-8)/(x^12-502*x^6+1). [Colin Barker, Jul 18 2012]

A041123 Denominators of continued fraction convergents to sqrt(70).

Original entry on oeis.org

1, 2, 3, 8, 11, 30, 491, 1012, 1503, 4018, 5521, 15060, 246481, 508022, 754503, 2017028, 2771531, 7560090, 123732971, 255026032, 378759003, 1012544038, 1391303041, 3795150120, 62113704961, 128022560042
Offset: 0

Views

Author

Keywords

Crossrefs

Programs

Formula

a(n) = 502*a(n-6)-a(n-12). G.f.: -(x^2-2*x-1)*(x^8+4*x^6+15*x^4+4*x^2+1)/ (x^12-502*x^6+1). [Colin Barker, Jul 18 2012]

A020827 Decimal expansion of 1/sqrt(70).

Original entry on oeis.org

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

Views

Author

Keywords

Examples

			0.11952286.. = 1/A010522.
		

Programs

  • Mathematica
    RealDigits[1/Sqrt[70],10,120][[1]] (* Harvey P. Dale, Jul 03 2017 *)

A171542 Decimal expansion of sqrt(27/70).

Original entry on oeis.org

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

Views

Author

R. J. Mathar, Dec 11 2009

Keywords

Comments

The absolute value of the Clebsch-Gordan coupling coefficient = <2 3/2 ; -1 3/2 | 5/2 1/2>.

Examples

			sqrt(27/70) = 3*sqrt(210)/70 = 0.621059003408118796016514178164...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[Sqrt[27/70],10,120][[1]] (* Harvey P. Dale, Apr 26 2011 *)

Formula

Showing 1-6 of 6 results.