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.

A248309 Egyptian fraction representation of sqrt(86) (A010537) using a greedy function.

Original entry on oeis.org

9, 4, 43, 2758, 10003866, 210627752029830, 52347107682242256851283255963, 2888760102328257324292867347514624728389388637643413378835, 73966122168790045965795439815232439142274674774329779302853705553926323866554092485061114120398281226411275872002645
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[ 86]]

A010159 Continued fraction for sqrt(86).

Original entry on oeis.org

9, 3, 1, 1, 1, 8, 1, 1, 1, 3, 18, 3, 1, 1, 1, 8, 1, 1, 1, 3, 18, 3, 1, 1, 1, 8, 1, 1, 1, 3, 18, 3, 1, 1, 1, 8, 1, 1, 1, 3, 18, 3, 1, 1, 1, 8, 1, 1, 1, 3, 18, 3, 1, 1, 1, 8, 1, 1, 1, 3, 18, 3, 1, 1, 1, 8, 1, 1, 1, 3, 18, 3, 1, 1, 1, 8, 1, 1
Offset: 0

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Author

Keywords

Examples

			9.273618495495703752516416073... = 9 + 1/(3 + 1/(1 + 1/(1 + 1/(1 + ...)))). - _Harry J. Smith_, Jun 10 2009
		

Crossrefs

Cf. A010537 (decimal expansion). - Harry J. Smith, Jun 10 2009

Programs

  • Mathematica
    ContinuedFraction[Sqrt[86],300] (* Vladimir Joseph Stephan Orlovsky, Mar 09 2011 *)
    PadRight[{9},120,{18,3,1,1,1,8,1,1,1,3}] (* Harvey P. Dale, Dec 13 2018 *)
  • Python
    from sympy import sqrt
    from sympy.ntheory.continued_fraction import continued_fraction_iterator
    def aupton(terms):
        gen = continued_fraction_iterator(sqrt(86))
        return [next(gen) for i in range(terms)]
    print(aupton(78)) # Michael S. Branicky, Sep 03 2021

A041152 Numerators of continued fraction convergents to sqrt(86).

Original entry on oeis.org

9, 28, 37, 65, 102, 881, 983, 1864, 2847, 10405, 190137, 580816, 770953, 1351769, 2122722, 18333545, 20456267, 38789812, 59246079, 216528049, 3956750961, 12086780932, 16043531893, 28130312825, 44173844718, 381521070569, 425694915287, 807215985856
Offset: 0

Views

Author

Keywords

Crossrefs

Programs

  • Mathematica
    Numerator[Convergents[Sqrt[86], 30]] (* Vincenzo Librandi, Oct 29 2013 *)

Formula

G.f.: -(x^19 -9*x^18 +28*x^17 -37*x^16 +65*x^15 -102*x^14 +881*x^13 -983*x^12 +1864*x^11 -2847*x^10 -10405*x^9 -2847*x^8 -1864*x^7 -983*x^6 -881*x^5 -102*x^4 -65*x^3 -37*x^2 -28*x -9) / (x^20 -20810*x^10 +1). - Colin Barker, Nov 10 2013

Extensions

More terms from Colin Barker, Nov 10 2013

A041153 Denominators of continued fraction convergents to sqrt(86).

Original entry on oeis.org

1, 3, 4, 7, 11, 95, 106, 201, 307, 1122, 20503, 62631, 83134, 145765, 228899, 1976957, 2205856, 4182813, 6388669, 23348820, 426667429, 1303351107, 1730018536, 3033369643, 4763388179, 41140475075, 45903863254, 87044338329, 132948201583, 485888943078
Offset: 0

Views

Author

Keywords

Crossrefs

Programs

  • Magma
    I:=[1, 3, 4, 7, 11, 95, 106, 201, 307, 1122, 20503, 62631, 83134, 145765, 228899, 1976957, 2205856, 4182813, 6388669, 23348820]; [n le 20 select I[n] else 20810*Self(n-10)-Self(n-20): n in [1..40]]; // Vincenzo Librandi, Dec 12 2013
  • Mathematica
    Denominator/@Convergents[Sqrt[86], 50] (* Vladimir Joseph Stephan Orlovsky, Jul 05 2011 *)
    CoefficientList[Series[-(x^18 - 3 x^17 + 4 x^16 - 7 x^15 + 11 x^14 - 95 x^13 + 106 x^12 - 201 x^11 + 307 x^10 - 1122 x^9 - 307 x^8 - 201 x^7 - 106 x^6 - 95 x^5 - 11 x^4 - 7 x^3 - 4 x^2 - 3 x - 1)/(x^20 - 20810 x^10 + 1), {x, 0, 30}], x] (* Vincenzo Librandi, Dec 12 2013 *)

Formula

G.f.: -(x^18 -3*x^17 +4*x^16 -7*x^15 +11*x^14 -95*x^13 +106*x^12 -201*x^11 +307*x^10 -1122*x^9 -307*x^8 -201*x^7 -106*x^6 -95*x^5 -11*x^4 -7*x^3 -4*x^2 -3*x-1) / (x^20-20810*x^10+1). - Colin Barker, Nov 13 2013
a(n) = 20810*a(n-10) - a(n-20). - Vincenzo Librandi, Dec 12 2013
Showing 1-4 of 4 results.