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.

A248286 Egyptian fraction representation of sqrt(61) (A010514) using a greedy function.

Original entry on oeis.org

7, 2, 4, 17, 702, 607877, 1343651924022, 4320622614714270261311118, 32109651275722538015654226404724112550695835225776, 2887634404082286927710711082091702089862802645035135042777568254515668100623050781361931122852713355
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[ 61]]

A010145 Continued fraction for sqrt(61).

Original entry on oeis.org

7, 1, 4, 3, 1, 2, 2, 1, 3, 4, 1, 14, 1, 4, 3, 1, 2, 2, 1, 3, 4, 1, 14, 1, 4, 3, 1, 2, 2, 1, 3, 4, 1, 14, 1, 4, 3, 1, 2, 2, 1, 3, 4, 1, 14, 1, 4, 3, 1, 2, 2, 1, 3, 4, 1, 14, 1, 4, 3, 1, 2, 2, 1, 3, 4, 1, 14, 1, 4, 3, 1, 2, 2, 1, 3, 4, 1, 14
Offset: 0

Views

Author

Keywords

Examples

			7.810249675906654394129722735... = 7 + 1/(1 + 1/(4 + 1/(3 + 1/(1 + ...)))). - _Harry J. Smith_, Jun 07 2009
		

Crossrefs

Cf. A010514 Decimal expansion. - Harry J. Smith, Jun 07 2009

Programs

  • Mathematica
    ContinuedFraction[Sqrt[61],300] (* Vladimir Joseph Stephan Orlovsky, Mar 08 2011 *)
    PadRight[{7},120,{14,1,4,3,1,2,2,1,3,4,1}] (* Harvey P. Dale, Mar 27 2013 *)
  • PARI
    { allocatemem(932245000); default(realprecision, 18000); x=contfrac(sqrt(61)); for (n=0, 20000, write("b010145.txt", n, " ", x[n+1])); } \\ Harry J. Smith, Jun 07 2009

A041106 Numerators of continued fraction convergents to sqrt(61).

Original entry on oeis.org

7, 8, 39, 125, 164, 453, 1070, 1523, 5639, 24079, 29718, 440131, 469849, 2319527, 7428430, 9747957, 26924344, 63596645, 90520989, 335159612, 1431159437, 1766319049, 26159626123, 27925945172, 137863406811, 441516165605, 579379572416, 1600275310437
Offset: 0

Views

Author

Keywords

Crossrefs

Programs

  • Mathematica
    Numerator[Convergents[Sqrt[61], 30]] (* Vincenzo Librandi, Oct 29 2013 *)

Formula

G.f.: -(x^21 -7*x^20 +8*x^19 -39*x^18 +125*x^17 -164*x^16 +453*x^15 -1070*x^14 +1523*x^13 -5639*x^12 +24079*x^11 +29718*x^10 +24079*x^9 +5639*x^8 +1523*x^7 +1070*x^6 +453*x^5 +164*x^4 +125*x^3 +39*x^2 +8*x +7) / (x^22 +59436*x^11 -1). - Colin Barker, Nov 12 2013

Extensions

More terms from Colin Barker, Nov 12 2013

A041107 Denominators of continued fraction convergents to sqrt(61).

Original entry on oeis.org

1, 1, 5, 16, 21, 58, 137, 195, 722, 3083, 3805, 56353, 60158, 296985, 951113, 1248098, 3447309, 8142716, 11590025, 42912791, 183241189, 226153980, 3349396909, 3575550889, 17651600465, 56530352284, 74181952749, 204894257782, 483970468313, 688864726095
Offset: 0

Views

Author

Keywords

Crossrefs

Programs

  • Magma
    I:=[1, 1, 5, 16, 21, 58, 137, 195, 722, 3083, 3805, 56353, 60158, 296985, 951113, 1248098, 3447309, 8142716, 11590025, 42912791, 183241189, 226153980]; [n le 22 select I[n] else 59436*Self(n-11)+Self(n-22): n in [1..40]]; // Vincenzo Librandi, Dec 11 2013
  • Mathematica
    Denominator[Convergents[Sqrt[61], 30]] (* Vincenzo Librandi, Dec 11 2013 *)

Formula

G.f.: -(x^20 -x^19 +5*x^18 -16*x^17 +21*x^16 -58*x^15 +137*x^14 -195*x^13 +722*x^12 -3083*x^11 +3805*x^10 +3083*x^9 +722*x^8 +195*x^7 +137*x^6 +58*x^5 +21*x^4 +16*x^3 +5*x^2 +x +1) / (x^22 +59436*x^11 -1). - Colin Barker, Nov 12 2013
a(n) = 59436*a(n-11) + a(n-22). - Vincenzo Librandi, Dec 11 2013

Extensions

More terms from Colin Barker, Nov 12 2013
Showing 1-4 of 4 results.