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 11-17 of 17 results.

A011042 Decimal expansion of 4th root of 48.

Original entry on oeis.org

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

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Author

Keywords

Programs

Formula

Equals 2*A011002. [From R. J. Mathar, Feb 04 2009]

A018052 Powers of fourth root of 3 rounded to nearest integer.

Original entry on oeis.org

1, 1, 2, 2, 3, 4, 5, 7, 9, 12, 16, 21, 27, 36, 47, 62, 81, 107, 140, 185, 243, 320, 421, 554, 729, 959, 1263, 1662, 2187, 2878, 3788, 4985, 6561, 8635, 11364, 14956, 19683, 25904, 34092, 44868, 59049, 77713
Offset: 0

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Author

Keywords

Crossrefs

Programs

  • Mathematica
    Floor[# + 1/2]&/@((Power[3, (4)^-1])^Range[0, 50]) (* Vincenzo Librandi, Apr 13 2017 *)
    Round[Surd[3,4]^Range[0,50]] (* Harvey P. Dale, Apr 13 2022 *)

A159824 Continued fraction for Pi^Pi (cf. A073233).

Original entry on oeis.org

36, 2, 6, 9, 2, 1, 2, 5, 1, 1, 6, 2, 1, 291, 1, 38, 50, 1, 2, 5, 4, 1, 2, 2, 1, 5, 1, 4, 13, 2, 1, 4, 3, 3, 1, 2, 25, 1, 1, 1, 2, 2, 1, 1, 1, 2, 2, 3, 1, 43, 1, 2, 7, 3, 1, 1, 1, 2, 4, 2, 1, 1, 3, 1, 3, 3, 2, 2, 16, 3, 5, 2, 1, 5, 2, 1, 10, 1, 1, 3, 1, 13, 1, 1, 3, 1, 10, 4, 1, 1, 1, 38, 1, 2, 2, 1, 1, 3
Offset: 0

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Author

Harry J. Smith, Apr 30 2009

Keywords

Examples

			36.4621596072079117709908260... = 36 + 1/(2 + 1/(6 + 1/(9 + 1/(2 + ...)))).
		

Crossrefs

Programs

  • Mathematica
    ContinuedFraction[Pi^Pi,200] (* Vladimir Joseph Stephan Orlovsky, Jul 20 2010 *)
  • PARI
    { allocatemem(932245000); default(realprecision, 21000); x=contfrac(Pi^Pi); for (n=1, 20001, write("b159824.txt", n-1, " ", x[n])); }

Extensions

Edited by N. J. A. Sloane, Jul 22 2010

A179275 Decimal expansion of 2*sqrt(Pi)/3^(1/4).

Original entry on oeis.org

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

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Author

Rick L. Shepherd, Jul 07 2010

Keywords

Comments

Also the side length of an equilateral triangle with area Pi (A000796), the area of a unit circle.
The area of an equilateral triangle with side length s is (sqrt(3)/4)s^2 = A120011*s^2, so A120011*(this constant)^2 = A000796.

Examples

			2.693547374177196721238160475092328667088670807308015892399206645495191607305...
		

Crossrefs

Cf. A002161 (sqrt(Pi)), A011002 (3^1/4), A000796 (Pi), A002194 (sqrt(3)), A120011 (sqrt(3)/4).

Programs

  • Mathematica
    RealDigits[2*Sqrt[Pi]/3^(1/4), 10, 100][[1]] (* G. C. Greubel, Mar 24 2017 *)
  • PARI
    2*sqrt(Pi)/3^(1/4)

Formula

2*sqrt(Pi)/3^(1/4) = 2*A002161/A011002.

A269430 Decimal expansion of (1 + Pi)/2.

Original entry on oeis.org

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

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Author

Jani Melik, Feb 26 2016

Keywords

Examples

			2.0707963267948966192313216916397514420985846996875529...
		

Crossrefs

Programs

  • PARI
    (1 + Pi)/2 \\ Altug Alkan, Apr 07 2016
  • Sage
    N((1+pi)/2, digits=110)
    

Formula

Equals A096444 + 1 or A019669 + 1/2.
Equals Sum_{k>=0} 2^k/binomial(2*k+2,k). - Amiram Eldar, Jun 30 2020

A358186 Decimal expansion of the positive real root r of 3*x^4 - 1.

Original entry on oeis.org

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

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Author

Wolfdieter Lang, Dec 04 2022

Keywords

Comments

The other roots are -r and the complex conjugate pair r*i and -r*i.

Examples

			0.75983568565159254733118775065454533539677344888731031861128865370032223317...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[Surd[1/3, 4], 10, 120][[1]] (* Amiram Eldar, Dec 07 2022 *)

Formula

r = (1/3)^(1/4) = (1/3)*27^(1/4).
Equals A011022/3.
Equals exp(-arctanh(1/2)/2). - Amiram Eldar, Jul 06 2023
Equals 1/A011002. - Jason Yuen, Jul 27 2024

A369499 Decimal expansion of exp(sqrt(3)*Pi/18)/3^(1/4).

Original entry on oeis.org

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

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Author

Amiram Eldar, Jan 25 2024

Keywords

Examples

			1.02803254168957677046288435785772167789241862654002...
		

Crossrefs

Cf. A011002.

Programs

  • Mathematica
    RealDigits[Exp[Sqrt[3]*Pi/18]/3^(1/4), 10, 120][[1]]
  • PARI
    exp(sqrt(3)*Pi/18)/sqrtn(3, 4)

Formula

Equals Product_{k>=1} (1 + 2*exp(-k*Pi*sqrt(3)) * cosh(k*Pi/sqrt(3))) (Stadler, 2012).
Previous Showing 11-17 of 17 results.