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 1-3 of 3 results.

A041978 Numerators of continued fraction convergents to sqrt(512).

Original entry on oeis.org

22, 23, 45, 68, 181, 1154, 12875, 78404, 169683, 248087, 417770, 665857, 29715478, 30381335, 60096813, 90478148, 241053109, 1536796802, 17145817931, 104411704388, 225969226707, 330380931095, 556350157802, 886731088897, 39572518069270, 40459249158167
Offset: 0

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Author

Keywords

Crossrefs

Programs

  • Mathematica
    Numerator[Convergents[Sqrt[512], 30]] (* Harvey P. Dale, Apr 09 2012 *)

Formula

G.f.: -(x^23 -22*x^22 +23*x^21 -45*x^20 +68*x^19 -181*x^18 +1154*x^17 -12875*x^16 +78404*x^15 -169683*x^14 +248087*x^13 -417770*x^12 -665857*x^11 -417770*x^10 -248087*x^9 -169683*x^8 -78404*x^7 -12875*x^6 -1154*x^5 -181*x^4 -68*x^3 -45*x^2 -23*x -22) / ((x^6 -34*x^3 +1)*(x^6 +34*x^3 +1)*(x^12 +1154*x^6 +1)). - Colin Barker, Nov 28 2013
Limit n->infinity a(n)^(1/n) = (1+sqrt(2))^(4/3) = 3.2386765777... - Vaclav Kotesovec, Nov 28 2013

Extensions

More terms from Colin Barker, Nov 28 2013

A041979 Denominators of continued fraction convergents to sqrt(512).

Original entry on oeis.org

1, 1, 2, 3, 8, 51, 569, 3465, 7499, 10964, 18463, 29427, 1313251, 1342678, 2655929, 3998607, 10653143, 67917465, 757745258, 4614389013, 9986523284, 14600912297, 24587435581, 39188347878, 1748874742213, 1788063090091, 3536937832304, 5325000922395
Offset: 0

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Author

Keywords

Crossrefs

Programs

  • Mathematica
    Denominator[Convergents[Sqrt[512], 30]] (* Vincenzo Librandi, Jan 11 2014 *)

Formula

G.f.: -(x^22 -x^21 +2*x^20 -3*x^19 +8*x^18 -51*x^17 +569*x^16 -3465*x^15 +7499*x^14 -10964*x^13 +18463*x^12 -29427*x^11 -18463*x^10 -10964*x^9 -7499*x^8 -3465*x^7 -569*x^6 -51*x^5 -8*x^4 -3*x^3 -2*x^2 -x -1) / ((x^6 -34*x^3 +1)*(x^6 +34*x^3 +1)*(x^12 +1154*x^6 +1)). - Colin Barker, Nov 28 2013

Extensions

More terms from Colin Barker, Nov 28 2013

A190567 Continued fraction expansion of 46*sqrt(46).

Original entry on oeis.org

311, 1, 76, 1, 622, 1, 76, 1, 622, 1, 76, 1, 622, 1, 76, 1, 622, 1, 76, 1, 622, 1, 76, 1, 622, 1, 76, 1, 622, 1, 76, 1, 622, 1, 76, 1, 622, 1, 76, 1, 622, 1, 76, 1, 622, 1, 76, 1, 622, 1, 76, 1, 622, 1, 76, 1, 622, 1, 76, 1, 622, 1, 76, 1, 622, 1, 76, 1, 622, 1, 76, 1, 622
Offset: 0

Views

Author

Bruno Berselli, May 13 2011

Keywords

Crossrefs

Programs

  • Magma
    [311] cat &cat[ [1,76,1,622]: n in [1..18] ];
    
  • Magma
    I:=[311,1,76,1,622]; [n le 5 select I[n] else Self(n-4): n in [1..80]]; // Vincenzo Librandi, Jun 14 2013
  • Mathematica
    ContinuedFraction[46 Sqrt[46], 80] (* or *) PadRight[{311}, 80, {622, 1, 76, 1}]
    CoefficientList[Series[(311 + x + 76 x^2 + x^3 + 311 x^4) / (1 - x^4), {x, 0, 100}], x] (* Vincenzo Librandi, Jun 14 2013 *)
  • PARI
    a(n)=if(n,[622,1,76,1][n%4+1],311) \\ Charles R Greathouse IV, May 13 2011
    

Formula

G.f.: (311+x+76*x^2+x^3+311*x^4)/(1-x^4).
a(n) = 1+3*(1+(-1)^n)*(116+91*i^n)/2 with n>0, i=sqrt(-1) and a(0)=311.
a(n) = (-1513*(n mod 4)+575*((n+1) mod 4)+125*((n+2) mod 4)+2213*((n+3) mod 4))/12 for n>0.
a(n) = a(n-4), n>=5. - Vincenzo Librandi, Jun 14 2013
Showing 1-3 of 3 results.