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.

A130590 Decimal expansion of the mean Euclidean distance from a point in the unit 3D cube to a given vertex of the cube.

Original entry on oeis.org

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

Views

Author

R. J. Mathar, Aug 10 2007

Keywords

Examples

			0.960591956455052959425107951...
		

Crossrefs

Analogous constants: A244921 (square), A254979 (4-cube).

Programs

  • Maple
    evalf( sqrt(3)/4+log(2+sqrt(3))/2-Pi/24);
  • Mathematica
    RealDigits[Sqrt[3]/4 + Log[2+Sqrt[3]]/2 - Pi/24, 10, 120][[1]] (* Amiram Eldar, Jun 04 2023 *)

Formula

Equals sqrt(3)/4 + log(2+sqrt(3))/2 - Pi/24 = A010527/2 + A065914/2 - A019691.
Equals 2 * A135691. - Amiram Eldar, Jun 04 2023

Extensions

Name corrected by Amiram Eldar, Jun 04 2023

A117653 Coefficients in an asymptotic expansion for mean distance from origin of a point uniformly distributed over the n-dimensional unit cube [0,1]^n (numerators).

Original entry on oeis.org

1, -1, -13, -101, -37533
Offset: 0

Views

Author

N. J. A. Sloane, Apr 12 2006

Keywords

Examples

			(n/3)^(1/2)*(1-n/10 -13n^2/280 - ...)
		

Crossrefs

A117654 Coefficients in an asymptotic expansion for mean distance from origin of a point uniformly distributed over the n-dimensional unit cube [0,1]^n (denominators).

Original entry on oeis.org

1, 10, 280, 2800, 1232000
Offset: 0

Views

Author

N. J. A. Sloane, Apr 12 2006

Keywords

Examples

			(n/3)^(1/2)*(1-n/10 -13n^2/280 - ...)
		

Crossrefs

A254980 Decimal expansion of the mean reciprocal Euclidean distance from a point in a unit 4D cube to a given vertex of the cube (named B_4(-1) in Bailey's paper).

Original entry on oeis.org

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

Views

Author

Jean-François Alcover, Feb 11 2015

Keywords

Examples

			0.96741202124116589866183643817815839013593700929996...
		

Crossrefs

Programs

  • Mathematica
    Ti2[x_] := (I/2)*(PolyLog[2, -I*x] - PolyLog[2, I*x]); B4[-1] = 2*Log[3] - (2/3) * Catalan + 2*Ti2[3 - 2*Sqrt[2]] - Sqrt[8]*ArcTan[1/Sqrt[8]] // Re; RealDigits[ B4[-1], 10, 104] // First
  • Python
    from mpmath import *
    mp.dps=105
    x=3 - 2*sqrt(2)
    Ti2x=(j/2)*(polylog(2, -j*x) - polylog(2, j*x))
    C = 2*log(3) - (2/3)*catalan + 2*Ti2x - sqrt(8) * atan(1/sqrt(8))
    print([int(n) for n in list(str(C.real)[2:-1])]) # Indranil Ghosh, Jul 03 2017

Formula

B_4(-1) = 2*log(3) - (2/3)*Catalan + 2*Ti_2(3-2*sqrt(2)) - sqrt(8) * arctan( 1/sqrt(8) ), where Ti_2(x) = (i/2)*(polylog(2, -i*x) - polylog(2, i*x)) (Ti_2 is the inverse tangent integral function).

Extensions

Name corrected by Amiram Eldar, Jun 04 2023
Showing 1-4 of 4 results.