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.

A060804 Continued fraction for 2*zeta(3).

Original entry on oeis.org

2, 2, 2, 9, 3, 10, 1, 4, 18, 1, 3, 5, 3, 1, 3, 3, 1, 1, 5, 3, 8, 1, 2, 1, 62, 1, 1, 1, 3, 2, 2, 1, 1, 5, 3, 1, 8, 2, 2, 34, 7, 1, 1, 5, 1, 2, 3, 3, 14, 9, 214, 11, 8, 23, 1, 8, 2, 10, 2, 2, 2, 1, 1, 6, 1, 8, 2, 1, 9, 2, 1, 11, 1, 3, 3, 4, 1, 28, 6, 1, 28, 1, 15, 1, 1, 1, 2
Offset: 0

Views

Author

N. J. A. Sloane, Apr 29 2001

Keywords

Examples

			2.404113806319188570799476323... = 2 + 1/(2 + 1/(2 + 1/(9 + 1/(3 + ...)))). - _Harry J. Smith_, Jul 12 2009
		

Crossrefs

Cf. A060805, A060806, A060807, A060808 (convergents).
Cf. A152648 (decimal expansion).

Programs

  • Maple
    Digits := 100: t1 := evalf(2*Zeta(3)); convert(t1,confrac);
  • Mathematica
    ContinuedFraction[2 Zeta[3],90] (* Harvey P. Dale, Apr 25 2025 *)
  • PARI
    { allocatemem(932245000); default(realprecision, 21000); x=contfrac(2*zeta(3)); for (n=1, 20000, write("b060804.txt", n-1, " ", x[n])); } \\ Harry J. Smith, Jul 12 2009

Extensions

Offset changed by Andrew Howroyd, Jul 10 2024

A060805 Numerators of special continued fraction for 2*zeta(3).

Original entry on oeis.org

2, 1, 2, 1, 4, 2, 6, 4, 9, 6, 12, 9, 16, 12, 20, 16, 25, 20, 30, 25, 36, 30, 42, 36, 49, 42, 56, 49, 64, 56, 72, 64, 81, 72, 90, 81, 100, 90, 110, 100, 121, 110, 132, 121, 144, 132, 156, 144, 169, 156, 182, 169, 196, 182, 210, 196, 225, 210, 240, 225, 256, 240, 272, 256
Offset: 1

Views

Author

N. J. A. Sloane, Apr 29 2001

Keywords

References

  • Y. V. Nesterenko, A few remarks on zeta(3), Mathematical Notes, 59 (No. 6, 1996), 625-636.

Crossrefs

Cf. A152648 (2*zeta(3)).

Programs

  • Maple
    A060805 := proc(n) local nshf,k ; if n <= 2 then op(n,[2,1]) ; else nshf := n-1 ; k := floor(nshf/4) ; if nshf mod 4 = 1 then k*(k+1) ; elif nshf mod 4 = 0 then (k+1)^2 ; elif nshf mod 4 = 2 then (k+1)*(k+2) ; else (k+1)^2 ; end if; end if; end proc: seq(A060805(n),n=1..80) ; # R. J. Mathar, Jul 31 2010
  • Mathematica
    Join[{2, 1}, LinearRecurrence[{1, 1, -1, 1, -1, -1, 1}, {2, 1, 4, 2, 6, 4, 9}, 100]] (* Jean-François Alcover, Apr 01 2020 *)

Formula

a(n) = A008733(n-1), n>2. - R. J. Mathar, Jul 31 2010

Extensions

More terms from R. J. Mathar, Jul 31 2010

A060808 Denominators of ordinary continued fraction convergents for 2*zeta(3).

Original entry on oeis.org

1, 2, 5, 47, 146, 1507, 1653, 8119, 147795, 155914, 615537, 3233599, 10316334, 13549933, 50966133, 166448332, 217414465, 383862797, 2136728450, 6794048147, 56489113626, 63283161773, 183055437172, 246338598945, 15456048571762
Offset: 0

Views

Author

N. J. A. Sloane, Apr 29 2001

Keywords

Examples

			2, 5/2, 12/5, 113/47, 351/146, 3623/1507, 3974/1653, ...
		

References

  • Y. V. Nesterenko, Some remarks on zeta(3), Mathematical Notes, 59 (No. 6, 1996), 625-636.

Crossrefs

Cf. A060804, A060805, A060806, A060807 (numerators).

Programs

  • Maple
    Digits := 100: t1 := evalf(2*Zeta(3)); cfrac(t1,l1,l2); l1;

Extensions

More terms from Vladeta Jovovic, Apr 29 2001
Offset changed by Andrew Howroyd, Jul 10 2024
Showing 1-3 of 3 results.