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.

Previous Showing 21-29 of 29 results.

A020768 Decimal expansion of 1/sqrt(11).

Original entry on oeis.org

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

Views

Author

N. J. A. Sloane

Keywords

Comments

1/sqrt(11) = 0.3015113445777636226468120669700624258115535041444866906416983769196804220553... [Vladimir Joseph Stephan Orlovsky, May 27 2010]

Links

Crossrefs

Cf. A010468.

Programs

A083335 a(n) = 12*a(n-2) - 25*a(n-4) with initial terms 1,1,7,12.

Original entry on oeis.org

1, 1, 7, 12, 59, 119, 533, 1128, 4921, 10561, 45727, 98532, 425699, 918359, 3965213, 8557008, 36940081, 79725121, 344150647, 742776252, 3206305739, 6920186999, 29871902693, 64472837688, 278305188841, 600669377281, 2592864698767, 5596211585172, 24156746664179
Offset: 0

Views

Author

Mario Catalani (mario.catalani(AT)unito.it), Apr 26 2003

Keywords

Comments

A083334(n)/a(n) converges to sqrt(11).

Links

Crossrefs

Cf. A010468 (sqrt(11)), A083334.

Programs

  • Mathematica
    CoefficientList[Series[(1+x-5x^2)/(1-12x^2+25x^4), {x, 0, 30}], x]
LinearRecurrence[{0,12,0,-25},{1,1,7,12},30] (* Harvey P. Dale, Mar 19 2013 *)

Formula

G.f.: (1 + x - 5*x^2) / (1 - 12*x^2 + 25*x^4).

A172274 a(n) = floor(n*(sqrt(13)-sqrt(11))).

Original entry on oeis.org

0, 0, 0, 0, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 6, 6, 6, 6, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 10, 10, 10, 10, 11, 11, 11, 12, 12, 12, 13, 13, 13, 13, 14, 14, 14, 15, 15, 15, 15, 16, 16, 16, 17, 17, 17, 17, 18, 18, 18, 19, 19, 19, 19, 20, 20, 20, 21, 21, 21, 21, 22, 22, 22, 23
Offset: 0

Views

Author

Vincenzo Librandi, Jan 30 2010

Keywords

Links

Crossrefs

Cf. A010470, A010468, A172264, A172266-A172270, A172272-A172278.

Programs

  • Magma
    [Floor(n*(Sqrt(13)-Sqrt(11))): n in [0..80]]; // Vincenzo Librandi, Aug 01 2013
  • Mathematica
    With[{c = Sqrt[13] - Sqrt[11]}, Floor[c Range[0, 80]]] (* Vincenzo Librandi, Aug 01 2013 *)

Formula

a(n) = floor(n*(A010470 - A010468)). - Rick L. Shepherd, Jun 17 2010

Extensions

Edited by Rick L. Shepherd, Jun 17 2010

A177345 Decimal expansion of sqrt(2805).

Original entry on oeis.org

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

Views

Author

Klaus Brockhaus, May 06 2010

Keywords

Comments

Continued fraction expansion of sqrt(2805) is 52 followed by (repeat 1, 25, 2, 25, 1, 104).
sqrt(2805) = sqrt(3)*sqrt(5)*sqrt(11)*sqrt(17).

Examples

			sqrt(2805) = 52.96225070746144187131...

Crossrefs

Cf. A002194 (decimal expansion of sqrt(3)), A002163 (decimal expansion of sqrt(5)), A010468 (decimal expansion of sqrt(11)), A010473 (decimal expansion of sqrt(17)), A177344 (decimal expansion of (33+sqrt(2805))/66).

A187109 Decimal expansion of sqrt(2/11).

Original entry on oeis.org

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

Views

Author

Vladimir Joseph Stephan Orlovsky, Mar 05 2011

Keywords

Examples

			sqrt(2/11) = 0.42640143271122086859687546486767875278074803212834...

Links

Crossrefs

Cf. A002193 (sqrt(2)), A010468 (sqrt(11)).

Programs

  • Magma
    SetDefaultRealField(RealField(100)); Sqrt(2/11); // G. C. Greubel, Oct 02 2018
  • Mathematica
    RealDigits[N[Sqrt[2/11],300]][[1]]
  • PARI
    sqrt(2/11) \\ Charles R Greathouse IV, Apr 25 2016

A382002 Decimal expansion of the isoperimetric quotient of a triakis tetrahedron.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Mar 16 2025

Keywords

Comments

For the definition of isoperimetric quotient of a solid, references and links, see A381684.

Examples

			0.64583578984055654756565980578430049996817368590574...

Links

Crossrefs

Cf. A378204 (surface area), A378205 (volume).
Cf. A000796, A010468, A381684.

Programs

  • Mathematica
    First[RealDigits[15/22*Pi/Sqrt[11], 10, 100]]

Formula

Equals 36*Pi*A378205^2/(A378204^3).
Equals (15/22)*(Pi/sqrt(11)) = (15/22)*(A000796/A010468).

A385448 Decimal expansion of sqrt(5 + 7*phi)/sqrt(11), with the golden section phi = A001622.

Original entry on oeis.org

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

Views

Author

Wolfdieter Lang, Jul 01 2025

Keywords

Comments

This equals the ratio length(Z, D_1)/s, with the fixed point of a complex loxodromic map w mapping iteratively golden triangles, starting with the one inscribed in a circumcircle with center ot the origin of the complex plane, the top vertex D_1 = i (the complex unit) and the base D_2 = (s - phi*i)/2, D_3 = (-s - phi*i)/2, with s = A182007.
See A385445 for details and a linked paper.

Examples

			1.218278887359662291535460267917274745203687400531554...

Crossrefs

Cf. A001622, A182007, A010468, A385445.

Programs

  • Mathematica
    RealDigits[Sqrt[(5 + 7*GoldenRatio)/11], 10, 120][[1]] (* Amiram Eldar, Jul 02 2025 *)

Formula

Equals sqrt(5 + 7*phi)/sqrt(11) = sqrt(5 + 7*phi)/A010468.
Equals A385447/(A010468*A182007).

A176515 Decimal expansion of (9+3*sqrt(11))/2.

Original entry on oeis.org

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

Views

Author

Klaus Brockhaus, Apr 23 2010

Keywords

Comments

Continued fraction expansion of (9+3*sqrt(11))/2 is A010699 preceded by 9.

Examples

			(9+3*sqrt(11))/2 = 9.47493718553309977367...

Crossrefs

Cf. A010468 (decimal expansion of sqrt(11)), A010699 (repeat 2, 9).

A378791 Decimal expansion of 2/(5*sqrt(11)).

Original entry on oeis.org

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

Views

Author

Stefano Spezia, Dec 07 2024

Keywords

Examples

			0.12060453783110544905872482678802497032462140165779...

References

  • Steven R. Finch, Mathematical Constants, Encyclopedia of Mathematics and its Applications, vol. 94, Cambridge University Press, 2003, Section 2.23, p. 174.

Links

Crossrefs

Cf. A010468.

Programs

  • Mathematica
    RealDigits[2/(5Sqrt[11]),10,100][[1]]
Previous Showing 21-29 of 29 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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