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.

A300690 Decimal expansion of sqrt(Pi^2/8 - 1).

Original entry on oeis.org

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

Views

Author

Keywords

Comments

Also the total harmonic distortion (THD) of a square wave, see formula (11) in the Blagouchine & Moreau link.

Examples

			0.4834258476086790990137326370639317022328017276651459...
		

Crossrefs

Programs

  • MATLAB
    format long; sqrt(pi^2/8-1)
  • Maple
    evalf(sqrt((1/8)*Pi^2-1), 120)
  • Mathematica
    RealDigits[Sqrt[Pi^2/8 - 1], 10, 120][[1]]
  • PARI
    default(realprecision, 120); sqrt(Pi^2/8-1)
    

A300714 Decimal expansion of the total harmonic distortion (THD) of the sawtooth signal filtered by a 1st-order low-pass filter.

Original entry on oeis.org

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

Views

Author

Keywords

Comments

See formula (33) in the Blagouchine & Moreau link.

Examples

			0.3694861820952043731200546914239769936602361586790838...
		

Crossrefs

Programs

  • MATLAB
    format long; sqrt(pi^2/3-pi*coth(pi))
  • Maple
    evalf(sqrt((1/3)*Pi^2-Pi*coth(Pi)), 120)
  • Mathematica
    RealDigits[Sqrt[Pi^2/3 - Pi*Coth[Pi]], 10, 120][[1]]
  • PARI
    default(realprecision, 120); sqrt(Pi^2/3-Pi/tanh(Pi))
    

Formula

Equals sqrt(Pi^2/3 - Pi*coth(Pi)).

A300727 Decimal expansion of the total harmonic distortion (THD) of the sawtooth signal filtered by a 2nd-order low-pass filter.

Original entry on oeis.org

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

Views

Author

Keywords

Comments

See formula (34) in Blagouchine & Moreau link.

Examples

			0.1811416137938290040802181055813016784438928351595635...
		

Crossrefs

Cf. A247719 (Pi/sqrt(2)), A300690, A300713, A300714.

Programs

  • MATLAB
    format long; sqrt(sqrt(pi*(cot(pi/sqrt(2))*coth(pi/sqrt(2))^2-cot(pi/sqrt(2))^2*coth(pi/sqrt(2))-cot(pi/sqrt(2))-coth(pi/sqrt(2)))/((cot(pi/sqrt(2))^2+coth(pi/sqrt(2))^2)*sqrt(2))+(1/3)*pi^2-1))
    
  • Maple
    evalf(sqrt(Pi*(cot(Pi/sqrt(2))*coth(Pi/sqrt(2))^2-cot(Pi/sqrt(2))^2*coth(Pi/sqrt(2))-cot(Pi/sqrt(2))-coth(Pi/sqrt(2)))/((cot(Pi/sqrt(2))^2+coth(Pi/sqrt(2))^2)*sqrt(2))+(1/3)*Pi^2-1), 120)
  • Mathematica
    RealDigits[Sqrt[Pi*(Cot[Pi/Sqrt[2]]*Coth[Pi/Sqrt[2]]^2-Cot[Pi/Sqrt[2]]^2*Coth[Pi/Sqrt[2]]-Cot[Pi/Sqrt[2]]-Coth[Pi/Sqrt[2]])/((Cot[Pi/Sqrt[2]]^2+Coth[Pi/Sqrt[2]]^2)*Sqrt[2])+(1/3)*Pi^2-1], 10, 120][[1]]
  • PARI
    s2=sqrt(2);
    A=Pi/s2;
    B=1+2/(exp(2*A)-1)
    C=1/tan(A);
    sqrt(Pi*(B^2*C-B*C^2-C-B)/((C^2+B^2)*s2) + Pi^2/3 - 1) \\ Charles R Greathouse IV, Mar 11 2018

Formula

Equals sqrt(Pi*(cot(Pi/sqrt(2))*coth(Pi/sqrt(2))^2-cot(Pi/sqrt(2))^2*coth(Pi/sqrt(2))-cot(Pi/sqrt(2))-coth(Pi/sqrt(2)))/((cot(Pi/sqrt(2))^2+coth(Pi/sqrt(2))^2)*sqrt(2))+(1/3)*Pi^2-1).

A300731 Decimal expansion of sqrt(Pi^4/96 - 1).

Original entry on oeis.org

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

Views

Author

Keywords

Comments

Also the total harmonic distortion (THD) of a triangle wave, see formula (14) in the Blagouchine & Moreau link.

Examples

			0.1211529265193047433149738747453528509885975440568532...
		

Crossrefs

Programs

  • MATLAB
    format long; sqrt(pi^4/96-1)
  • Maple
    evalf(sqrt((1/96)*Pi^4-1), 120)
  • Mathematica
    RealDigits[Sqrt[Pi^4/96 - 1], 10, 120][[1]]
  • PARI
    default(realprecision, 120); sqrt(Pi^4/96-1)
    
Showing 1-4 of 4 results.